Soldering frustration - Page 1
Forum section: electronics / beginners

author: cigmas
author_rank: Regular Contributor
timestamp: October 12, 2020, 10:23:50 pm
content: What am I doing wrong?I can't get the tip clean even on a new tip. I try tinning: put the tip in rosin, apply some rosin core solder, swipe in a metal sponge... and it comes out looking lumpy instead of wetting nicely, with solder sputtering around, and colored orange and blueish.The solder wick doesn't wick the solder, instead solder barely sticks to it in a lumpy way, even though the copper gets hot really quickly.Can small pieces of rosin be used instead of flux paste? Initially it seems to work ok but sometimes it leaves a nasty thick brown residue.I want to desolder four pins -- you can easily see which. But instead of the graceful 1-2 seconds that it takes for experienced solderers, I struggle with the solder melting but not lifting away, the area getting really hot and browned, solder sputtering around. I stopped before my frustration resulted in lifted pads.

author: HB9EVI
author_rank: Frequent Contributor
timestamp: October 12, 2020, 10:58:55 pm
content: just a guess: maybe the tip is too hot (faulty temperature regulation or setting too high). that could explain the solder just sputtering around and not being able to wet the tip

author: cigmas
author_rank: Regular Contributor
timestamp: October 12, 2020, 11:05:41 pm
content: The thought did cross my mind. The iron is a 35W basic unit with no temperature settings. Since the soldering tasks end up taking a long time, the iron stays on easily for 30+ minutes. I have a TS100 on the way, but I want to figure out if I'm doing something wrong before ruining more expensive tips.

author: Electro Fan
author_rank: Super Contributor
timestamp: October 12, 2020, 11:08:21 pm
content: What kind of solder are you using?

author: cigmas
author_rank: Regular Contributor
timestamp: October 12, 2020, 11:12:43 pm
content: I believe it's lead solder with a rosin core. No idea of brand or exact composition.

author: Electro Fan
author_rank: Super Contributor
timestamp: October 12, 2020, 11:20:01 pm
content: Any chance you can borrow another iron to see if you can isolate the problem (iron, tip, solder, or some thing else/technique)?

author: thinkfat
author_rank: Unknown
timestamp: October 12, 2020, 11:25:04 pm
content: This is the wrong tip. Try a thicker chisel-type tip. There is hardly any surface area that would be able to pick up solder and the tip is way to pointy to provide enough heat transfer capability. It is just the wrong tool for the job. Also, spend some money on a temperature regulated iron.PS: also too little flux and tip too hot. The joints look brittle and dry, the flux is burned and sputtered all over the place. The tip burns up the flux it touches and has to little contact surface to transfer the heat into the joint efficiently.

author: cigmas
author_rank: Regular Contributor
timestamp: October 12, 2020, 11:31:41 pm
content: In a few weeks the TS100 I ordered should arrive. Until then, no, I don't have access to another iron.Yes, this slim pointy tip is really frustrating to use, but how is that relevant when just trying to tin the tip?I got the temperature-regulated TS100 with the BC2 or small chisel-like tip and I'm hoping that will be easier to work with.

author: james_s
author_rank: Super Contributor
timestamp: October 12, 2020, 11:36:28 pm
content: It looks way, way too hot, the plating is flaking off of the tip. If it's not too hot then it's a poor quality tip.

author: thinkfat
author_rank: Unknown
timestamp: October 12, 2020, 11:37:24 pm
content: It's likely the temperature. You need enough flux to wet the tip and clean off oxidation. If your flux burns away too quickly, the tin will not wet the tip.

author: cigmas
author_rank: Regular Contributor
timestamp: October 12, 2020, 11:55:56 pm
content: My multimeter has a temperature probe apparently rated for -20 to 1000 C, so next time I might try using it to get a sense of the iron's temperature.As for the quality of the tips, I got 5 for ~ $2 on ebay a few years ago so anything is possible. I just noticed that the description said "Replaceable Iron Tool Solder Tips for Soldering Station 30W TSUS" but my iron is 35W. Could that be an issue?I don't have flux paste, but put the tip directly into the rosin. Is that equivalent/ok? The solder also has a rosin core.

author: andy3055
author_rank: Super Contributor
timestamp: October 13, 2020, 12:25:28 am
content: I think it is the flux you are using. It looks like the crystals that is used for sheet metal work. Some cheap junk not meant for electronic repairs. Use a good quality solder.

author: tooki
author_rank: Super Contributor
timestamp: October 13, 2020, 02:05:58 am
content: Quote from: cigmas on October 12, 2020, 11:12:43 pmIs it Chinese no-name solder? That stuff is a recipe for frustration, by all accounts. Do yourself a favor and buy some real solder. There are countless existing threads on choosing solder, so just look up some and get one of the suggested ones.

author: helius
author_rank: Super Contributor
timestamp: October 13, 2020, 03:02:13 am
content: Quote from: cigmas on October 12, 2020, 11:55:56 pmThey are not equivalent. By putting flux onto the work (and using a moderate temperature, like 350 C) you clean oxides off the work as the flux heats. By dipping the tip in flux, you aren't cleaning the work at all, since the flux only burns on the tip. Further, the burnt flux insulates the tip so heat transfer is reduced.You should never dip the tip in flux unless your goal is to ruin the tip. Tip tinning pastes are not just flux, they have metal particles that retin so burnt flux doesn't accumulate. But normal use of rosin-core solder to tin tips is always better unless the tips are very oxidized.You can try to rub off the burnt flux with a grit eraser (the kind made for removing ink) and tin the tip normally from now on. You might even need to use 500-grit sandpaper. You can see how badly burned flux sticks to the tip if allowed to do so.Also: I just noticed that under the burnt flux, your tips appear to be copper colored. They look like unplated tips, which haven't been common in the industry for 50 years. The copper always tarnishes and loses its ability to wet solder, so it needs to be sanded before every use. On small tips this means rapid destruction of the tips; it is not so bad on huge (1/2" and above) sheet metal tips.All electronic tips these days are iron plated and then tinned, so they do not have any copper coloring.

author: Shock
author_rank: Super Contributor
timestamp: October 13, 2020, 03:38:32 am
content: As Tooki said don't buy or use Chinese consumables they will only add to your problems.

author: james_s
author_rank: Super Contributor
timestamp: October 13, 2020, 05:29:03 am
content: Buy a decent iron, that doesn't have to mean an expensive iron, but one that is reputable. Then buy reputable brand solder and optionally flux although I rarely use extra flux unless I'm doing some types of rework. Junk tools used with junk supplies without the experience to evaluate what's going on is asking for trouble.

author: David Hess
author_rank: Super Contributor
timestamp: October 13, 2020, 08:04:48 am
content: The temperature is too hot; get a temperature controlled iron.

author: cigmas
author_rank: Regular Contributor
timestamp: October 15, 2020, 06:21:00 am
content: Thanks for all the answers.Taking a break might be one of the best cures for frustration. I got the pins desoldered. I think technique and flux were my main lacks. After getting some flux on the desoldering wick by putting it on the rosin and heating the copper with the iron, it was drawing the solder from the pins pretty well. The tip is still not great but I found having a blob of solder on it and using that as the contact point works better for quicker heat transfer than having too little. Too much of course makes a mess, especially if trying to desolder.Still, the flux (whether the rosin core in the solder or the rosin block) is bubbling and burning and leaving a brown residue. I think that bubbling is also what sends solder flying around. The solder itself melts and flows very well.How hot is too hot? Measuring at the thick part of the tip gave readings typically from 350 C to 390 C and isn't particularly stable. (Yes, I'm getting a regulated iron soon...)How should rosin / flux be used to avoid residue on the tip or work? What temperature would be better for this? Would a liquid preparation with rosin + alcohol be better?Does the metal sponge need to be cleaned, and if so, how? I think the tip is often coming out dirtier than it went in, with bits of "dirt" and spikes of solder sticking on it after poking the tip into the sponge.The tip is still not looking nice. The solder blobs on it with an orange tinge, and the rosin from the solder leaves brown/black residue on the tip.What I'm working with:More tip close-ups:Solder "dust" at the bottom of the tray, and plenty more stuck in the sponge:Finished job after desoldering the four pins, and later resoldering them. Notice the brown residue from the flux, and specks of flux and solder that sputtered around:Side note: There was much struggling for a while with being unable to free the pins despite removing most of the solder. I thought some solder must still be in the through hole or on the pins lower down, blocking their exit from the hole, and kept trying to remove more solder. Nope. Later I realized the round black plastic pegs (attached to the component with the pins) have expanded heads that didn't fit through their PCB holes. Using pliers to flatten them a bit got the component unstuck... it had nothing to do with soldering.

author: sleemanj
author_rank: Super Contributor
timestamp: October 15, 2020, 06:36:44 am
content: Iron too hot, way too hot is my theory here, look at the blue colour on those tip shafts, that got real hot I'd say.The flux you have is solid rosin, like "rosin up your bow" rosin. This is basically pine tree resin which has been reduced down by heat and set as a solid, is indeed the primary ingredient in most fluxes.But it's uncommon to use it in this form, it's not really very convenient, and as you see it leaves behind the brown skid marks. Instead you want to get some liquid or paste/gel type flux.With that said, you can dissolve some of the rosin in some isopropyl alcohol to make a liquid flux (it will take some time to dissolve).

author: helius
author_rank: Super Contributor
timestamp: October 15, 2020, 06:39:20 am
content: There's still a strange yellow color on the pictures of the tips, old and new. The color of tips should be that of tin: bright gray with no yellow. Can you tell us whether this is an effect of lighting, or your tips really are yellow?

author: cigmas
author_rank: Regular Contributor
timestamp: October 15, 2020, 06:57:59 am
content: Quote from: sleemanj on October 15, 2020, 06:36:44 amWould this not leave the brown residue? Can 70% isopropyl alcohol be used?Quote from: helius on October 15, 2020, 06:39:20 amI would say it's lighting and texture, but I'm not 100% sure. It's really tricky, and while staring at a new tip in person, I keep changing my mind whether the difference in tint is real or perception. It's not obviously yellow though.The used ones definitely have a yellow/orange tint on the tip and/or solder on it. Without solder the cone of the tip turns blue really quickly, similar to one of the used tips in the photo, but all over the cone.

author: tggzzz
author_rank: Super Contributor
timestamp: October 15, 2020, 07:35:39 am
content: Very old but very good videos on soldering:https://www.youtube.com/playlist?list=PL926EC0F1F93C1837not least because they show what happens when you get it wrong.They were made for a professional audience (=>time==money) when making, distributing and showing videos was difficult and expensive (=>plan carefully, edit carefully). Compare that with most yooboob vids

author: thinkfat
author_rank: Unknown
timestamp: October 15, 2020, 07:36:51 am
content: I think you did well with the tools you had at hand. Soaking the solder wick in flux certainly was the right move. Keeping a solder blob on the tip to help with heat transfer is a common technique, so thumbs up on this.But I'm afraid the limit is your tools. You can improve by using a better flux, but as long as you don't have a temperature regulated iron, it's not going to help much, the flux will burn up and sputter tin everywhere. Mixing your own liquid flux using IPA will only increase your problems here.

author: Ian.M
author_rank: Super Contributor
timestamp: October 15, 2020, 07:54:28 am
content: If you are patient and set a low value on your time and labor, you can make liquid flux from your rosin equal to any commercial Rosin R (unactivated) liquid flux, however its a PITA to make and in most developed countries it would be a far more rational choice to simply order some! 70% IPA will be problematic. Rosin + water will be a real mess, and even if it stratifies and you decant off the upper clear rosin + alcohol layer for use as flux, residual water will make it spit everywhere as soon as you touch the bit to the work. The alcohol doesn't have to be IPA, as Denatured Alcohol (ethanol), aka: Methylated Spirits in Commonwealth countries, can also be used to make liquid Rosin flux. The important thing is the water content which should be as low as reasonably possible. However, *DON'T* try to dry your IPA by salting out with common salt, as trace chloride contamination is highy undesirable in fluxes used for fine electronics work. If you need usable flux quickly, it helps to pound the rosin to a fairly fine powder before mixing it with the alcohol, stirring vigorously, and warming the mixture to help it dissolve, *WITHOUT* using any naked flame or other heat source that's an ignition risk. An unheated water bath filled with hot water is probably the safest option.Try wiping your bit on a damp (not wet - squeeze out excess water) cellulose sponge, after cleaning off the worst of the dross buildup on the brass turnings. Also, you need to turn off or reduce power to the iron if you aren't actively using it. A single pole 'torpedo' switch inline with the iron's cord with a 1N4007 diode across the switch is a cheap and easy way to reduce the power by 50%. Another option would be to use a light dimmer.If you wipe off dross and char on the brass turnings and add enough extra solder to coat the bit every time you put the iron back in the stand with the intention of leaving it there for more than a few seconds, and reduce power or turn it off if its going to be in the stand more than a couple of minutes, and every time you take it out of the stand, wipe off excess solder on the brass turnings then oxides on the damp sponge, you'll have a lot less trouble maintaining the bit of a non-temperature-controlled iron in well tinned, usable condition. You can get cellulose sponge in the cleaning aisle of most supermarkets. Check a fragment with a lighter flame to be certain it is cellulose sponge that will char rather than melt and not a plastic sponge which would melt allover your bit and ruin it! Wash it thoroughly with hot water and a little dish detergent, then squeeze out and rinse thoroughly, before use as a soldering sponge as the plasticizer added to keep it soft in the packet can damage your bit.

author: Psi
author_rank: Super Contributor
timestamp: October 15, 2020, 08:26:31 am
content: It will be one of the following, in no particular order- Iron way to hot and is damaging tips. (There is reason why proper soldering stations are temperature regulated.)- Iron tips are fake/3rd party copies or just plan bad and the metal plating is wrong (Very common issue, solder just wont stick)- For some reason the solder or flux you have contains a chemical that is destroying the tips very fast.- Your flux is simply bad flux (or not even flux at all)- Same with your solder.Also, I would recommend you spend ~US$35 on a china clone soldering station that uses Hakko T12 style tips.A few people I know have got them and the tip that comes with them was totally fine. But worst case you can buy a genuine hakko T12 for it. The clone units often come with the K style knife tip, which is actually really useful for big and tiny stuff. It's a good all purpose tip

author: Shock
author_rank: Super Contributor
timestamp: October 15, 2020, 10:13:52 am
content: If you have flux core solder you shouldn't need to use the rosin block. Without thoroughly cleaning the tip constantly rosin will burn on and around the tinned portion of the tip and build up an insulating layer making it harder for solder to bond. The hotter the tip the worse this problem will be and also increases the speed of oxides forming on surface of the solder.As a test melt solder on the tip and clean it quickly with the brass wool and then repeat this several times. Each time the solder should start to tin the tip better until the solder easily bonds.Eventually the surface should look like the below photo straight after cleaning (brightness depends on the solder alloy used). But as I mentioned if you have poor quality solder and brass wool it will be a struggle.

author: tooki
author_rank: Super Contributor
timestamp: October 15, 2020, 05:41:36 pm
content: Quote from: cigmas on October 15, 2020, 06:21:00 amHonestly, throw out that junk and buy proper materials (from an authorized dealer so you don't get counterfeit): name-brand solder, name-brand wick, name-brand flux (not just a hunk of rosin!), and of course a proper temp-controlled station.Nothing good comes from using the awful junk, as you've been experiencing.Bear in mind that quality supplies and gear don't have to cost a fortune. For example, Stannol makes a paste flux (165018) that costs just a few euros for a 50g tub. It works infinitely better than plain rosin and isn't corrosive (though as a halogenated flux, residues may be conductive and should be removed).

author: Ctrlocti
author_rank: Regular Contributor
timestamp: October 16, 2020, 01:37:19 pm
content: I find it weird that a cheap non-adjustable iron comes with replaceable tips. It's all trash anyway as you've noticed.Tangential question, what is the actual purpose of those thin needle nose tips? i find them useless but I guess they are good for something since all the major manufacturers produce them

author: tooki
author_rank: Super Contributor
timestamp: October 16, 2020, 06:43:46 pm
content: Quote from: Ctrlocti on October 16, 2020, 01:37:19 pmHuh? I’ve never seen a soldering iron where the tipwasn’treplaceable.

author: james_s
author_rank: Super Contributor
timestamp: October 16, 2020, 08:10:38 pm
content: Certainly all of the cheap firesticks I had when I was a kid had replaceable tips.I've never found a use for those needle point tips either, they lack enough thermal mass and conductivity to heat anything.

author: janoc
author_rank: Super Contributor
timestamp: October 16, 2020, 08:55:46 pm
content: Quote from: Ctrlocti on October 16, 2020, 01:37:19 pmHow would you replace a worn out tip? Especially on these cheap irons that eat them for lunch? (and a nail will likely do a better job that many of these "tips").What is almost guaranteed to fail is that set screw respectively the thread in that hole over time, though.

author: Ian.M
author_rank: Super Contributor
timestamp: October 16, 2020, 10:06:54 pm
content: The shape of the original bit doesn't look too bad - the cone is relatively stubby and it may even be a 1/16" hoof tip. Cleaning that one up with steel wool and re-tinningh its tip may even make the iron usable (for a fire-stick), however I agree with James_s that fine needle tips (i.e. all the O.P's replacement tips) are pointless <GROAN> due to the thermal conductivity issue even on a good temperature controlled iron. The only *LESS* useful tip on a firestick is the attached 1mm delight from Antex!Since the needle tips are pretty ineffective at best, one might as well take the worst of them and break the rule of never filing, grinding or using harsh abrasives on a plated soldering bit by filing it to a hoof (bevel) tip shape. A 30 deg angle 2mm wide flat should be usable, though as solder erodes bare copper, it will have to be kept dressed to shape and discarded once it gets too short to conveniently use. Tin the face, not the sides to make it easier to control the erosion and keep it dressed to shape. It wont be much fun to use (as its a PITA to keep a bare copper bit tinned and dressed to shape) compared to an appropriately shaped bit in a temperature controlled iron, but should keep the O.P. going until his replacement iron arrives and as a backup if he ever needs to fix the good iron.

author: cdev
author_rank: Super Contributor
timestamp: October 17, 2020, 01:36:52 am
content: I have always wanted to try doing this. Where can one get the rosin, what is a good source of it?It's a powerful antioxidant. That's why it works.Quote from: Ian.M on October 15, 2020, 07:54:28 amAn untrasonic cleaner might sonicate the resin greatly accelerating the dissoving process. Perhaps one could put it in a plastic bag to prevent the flux from coating the cleaner's basin.

author: cigmas
author_rank: Regular Contributor
timestamp: October 17, 2020, 03:08:36 am
content: Quote from: tggzzz on October 15, 2020, 07:35:39 amAbsolutely fantastic videos! I binge-watched it all and saved them for rewatching several more times. I especially like that they explain *why* and *when* specific tools and techniques should or should not be used.They also have another great playlist about repair:https://www.youtube.com/playlist?list=PL958FF32927823D12Even something as simple as removing a component is not as trivial as it might first appear. Now I see why I struggled so much to desolder more than one lead, especially on multilayer boards, and how techniques like increasing the thermal linkage area (effectively what a solder blob does) and using a desoldering pump would have been useful.Quote from: thinkfat on October 15, 2020, 07:36:51 amWhat is bad about the flux and why would IPA be a problem? What temperatures are needed to avoid burning/sputtering?Quote from: Ian.M on October 15, 2020, 07:54:28 amThanks for the detailed explanations. That's exactly what I was wondering about the water content. I'm now wishing I had gotten the 99% IPA I was eyeing, before recent events made stock rare and expensive.Generally, what's wrong with using solid rosin? Do liquid and paste flux have advantages other than the ease of application?Quote from: Ian.M on October 15, 2020, 07:54:28 amSo both the brass turnings and damp sponge are required.. it's not an either/or? Does it make a difference whether the iron is poke into or wiped on the brass turnings?Quote from: Psi on October 15, 2020, 08:26:31 amGood tips, and to add to it, I think the biggest factor is my knowledge and skill. Having said that, how hot is too hot for the tip? What determines a bad tip or flux?On the first use, the solder wets the new tips well, but very soon after the problems begin. Maybe temperature issues, maybe poor tip, maybe wrong use/maintenance, maybe... Also, I realized that the tips were described for 30W irons but my iron is 35W (I thought it was less). Could that be a problem?Quote from: Shock on October 15, 2020, 10:13:52 amI'm fairly confident the solder is good since it melts and flows well, but what is poor quality brass wool? Does the metal sponge need to be cleaned/maintained?When it was new, or when using new sections, it worked well to clean the tip of excess solder. But lately the iron comes out of the metal sponge dirtier than it went in. The process sends bits of solder and "dirt" stuck inside flying around the room and forming spikes on the tip.Quote from: tooki on October 15, 2020, 05:41:36 pmHonestly, I'm not likely to make changes without understanding why. A skilled surgeon could be more effective with a cheap kitchen knife than an amateur with the best scalpel. As frustrating as my current equipment may be, I'm sure a skilled solderer could make better use of it, and similarly, that a lack of knowledge and skill could be ineffective with, or even ruin, quality equipment.If the failure is understood, then the needs become clear. Right now I'm just stabbing in the dark. The information in the great playlists above makes a huge difference. It seems many don't get formal training on things seen as basic, like run-of-the-mill soldering, and are just expect to "know" it or "pick it up". At least that's the case for me.Actually before posting I looked for tutorials or FAQs on the subject in the forums and on youtube. Those soldering and repair playlists belong in a sticky!

author: Ctrlocti
author_rank: Regular Contributor
timestamp: October 17, 2020, 05:20:19 am
content: I don't know guys, I never got replacement tips for my firesticks. Maybe there was one or two extra in the packet that it came with? I honestly don't remember. You toss the iron once the tip craps out. They used to cost like 10$, my tips now cost more than that but they last a lot longer than a firestick. I probably got the shittiest of the shitty firesticks.OP you are fighting your tools and hampering your skill development. Get a better iron.

author: Ian.M
author_rank: Super Contributor
timestamp: October 17, 2020, 06:00:13 am
content: Traditionally one just used a damp cellulose sponge to wipe the bit on, however it needs washing out every day its used to keep it in reasonable condition, and in use, needs to be kept damp, but not wet, which in a hot low humidity environment can be a PITA. Also it typically lowers the bit temperature when used, which is desirable when using a non-temperature-controlled 'firestick' iron but less so with a temperature controlled iron. The thermal shock of the wet sponge is excellent for removing oxides from the bit, but some believe it shortens the life of the bit's plating. Its no good for removing well adhered heavy contamination from the bit.Brass wool or turnings is the modern alternative recommended by many manufacturers. Its better at removing heavy deposits, and when used with a temperature controlled iron, does an adequate job of removing oxides, without the thermal shock. You've got to keep it reasonably clean for it to be effective, shaking out dross regularly and rolling the ball of wool or turnings between your palms to loosen adhered dross. If you've been using a lot of rosin or synthetic resin flux, you may even need to wash it out in alcohol to remove excess, badly contaminated flux.Generally you don't need both, but a damp sponge isn't good at removing heavy contamination, so if you don't have brass turnings, you'll need some other way of rough-cleaning the bit when flux residues and char build up.Most commercial electronics grade liquid fluxes are rosin or synthetic resin + additives in alcohol. If the surfaces to be soldered are clean bright metal you generally don't meed the additives as they are only there to make the flux more active so its more effective at removing oxides from the surfaces. However some metals don't take solder readily and a more active flux is helpful. Solid rosin is less than ideal because you need the flux at the edge of the solder puddle on the joint, and if you try to carry it there on the bit, it will already be burnt and less effective by the time it gets there.I've owned the same Weller 'firestick' for over 40 years (though its less used nowadays), and use whatever bits I can find of the right diameter for it, irrespective of brand or nominal wattage, or even ones cut from copper rod. As long as the bit fits snugly for good thermal contact, but isn't tight in the hole (as it will jam as oxides build up) its OK. The bit must be inserted to the full depth of the hole in the element to get good heat transfer. No doubt there are some 'firesticks' that are so low quality they are essentially disposable, but that's due to buying dirt-cheap tool-shaped crap rather than real tools.

author: Ctrlocti
author_rank: Regular Contributor
timestamp: October 17, 2020, 06:09:00 am
content: Quote from: Ian.M on October 17, 2020, 06:00:13 amyeah I stopped using the sponge. I'll lightly tin the tip, immediately rub it in the brass and it's good to go. I do it every time I put the iron down so there's not too much time for stuff to build up on the tip.

author: james_s
author_rank: Super Contributor
timestamp: October 17, 2020, 06:39:52 am
content: Quote from: Ctrlocti on October 17, 2020, 05:20:19 amI used a 25W Radio Shack iron for about 15 years before I bought my Edsyn soldering station. Back then proper soldering stations were really expensive and it wasn't until ebay appeared and I was finally making decent money that I could afford to buy a good used station. Prior to that I'd replace the tip on my cheap iron every couple of years, Radio Shack sold the tips so they were easy to get and inexpensive.

author: Ctrlocti
author_rank: Regular Contributor
timestamp: October 17, 2020, 07:06:35 am
content: Quote from: james_s on October 17, 2020, 06:39:52 amYes it's amazing what 100-150$ gets you now. I'm still using a hakko fx888d, very happy with it

author: Vovk_Z
author_rank: Super Contributor
timestamp: October 17, 2020, 07:23:27 am
content: When I haven't had soldering station (with temperature contro) I made a voltage regulator, because my cheap 60W soldering iron was always too hot. And it started to be almost ok.And yes - ( it was said yet ) that tip on the TS photo is too thin. It is rather for SMD.

author: thinkfat
author_rank: Unknown
timestamp: October 17, 2020, 08:08:25 am
content: Quote from: cigmas on October 17, 2020, 03:08:36 amIt boils at low temperatures and residual IPA and water in the home-made flux gel will make the sputtering worse.I typically set my iron temperature to around 300°C, maybe a bit more, when using leaded solder. I increase it to maybe 350°C when I have to work on joints with a large thermal mass behind it, but only because the iron is not directly heated, it is a 30 years old Weller soldering station predating direct-heat tips.

author: Ctrlocti
author_rank: Regular Contributor
timestamp: October 17, 2020, 08:24:19 am
content: Quote from: thinkfat on October 17, 2020, 08:08:25 amhmm I use 360c for leaded solder on all my joints. 1second for the usual stuff, 2-3s for the big stuff.Too hot? I don't get splutter. SOmetimes I'll go to 370c and get in and out super fast.

author: Shock
author_rank: Super Contributor
timestamp: October 17, 2020, 09:18:27 am
content: Quote from: Ctrlocti on October 17, 2020, 06:09:00 amIf you have a difficult tip that is not tinning properly it can help to use the brass wool first to clean the tip thoroughly then apply solder again directly to the tip. Repeat this several times and you should notice it tinning and taking solder better each time.It seems counter intuitive but when not soldering for any prolonged period leave a layer of solder on the tip, the additional solder layer protects the tip from oxides and burnt on flux residue building up.

author: Shock
author_rank: Super Contributor
timestamp: October 17, 2020, 10:27:35 am
content: Quote from: cigmas on October 17, 2020, 03:08:36 amMost solder, brass wool and wick will contain flux. The quality and performance will vary widely especially with the cheap Chinese brands. Fake sponges, brass wool and solder/flux are a thing and toxic fumes are bad enough as it is with name brands. Once the brass wool is used up replace it.Chemtronics wick, Hakko brass wool (refills are part number 599-029) and Kester solder are good brands. Though a reel of good solder is a high upfront cost, like anything the more you use it the more it pays off.

author: Psi
author_rank: Super Contributor
timestamp: October 17, 2020, 12:10:15 pm
content: Quote from: cigmas on October 17, 2020, 03:08:36 amThere are some chemicals that will totally ruin a soldering iron tip within days or even hours. Because the temp is so hot the rate of reaction is super fast.Some plastics will do it. Never use your good iron tip to melt plastic.Acid core flux will do it but that usually takes longer, days to weeks.The technology that goes into soldering iron tips is quite advanced which requires good quality control.I've seen bad tips that last days coming from big name manufactures and genuine distributors, it's rare but not as rare as you think.For no-name china brands i've seen everything from tips that work 100% perfectly and last years to tips that last 5 min before solder wont stick any more.

author: tkamiya
author_rank: Super Contributor
timestamp: October 17, 2020, 02:05:19 pm
content: I don't know about temperature, but it reminds me of Radio Shack type iron where tips were plated with some unknown substance. Very hard to get it properly wet and flowing. Once messed up and oxidized, an only thing I could do is to file the plating off and go to bare copper.OP will be better off starting out with a good iron. Even genuine temperature controlled and ESD safe Hakko will go for about 100 dollars. Less expensive Chinese made ones are less than 50 dollars. Some of them are pretty good. I have one.Solder wicks.... again, Cheap ones are very hard to use. They don't have good affinity to solder for some reason, and wicking action doesn't take place. Good ones are expensive but it's very much worth the price. Alternative is possibly causing damage to PCB.There is something called "tip tinner" by Thermaltronics. This stuff works. One small jar will probably last you 10 years. Costs about $6 US.

author: james_s
author_rank: Super Contributor
timestamp: October 17, 2020, 05:12:58 pm
content: When I'm using wick that is old or some less than great brand I dip it in liquid flux, I find that makes even cheap wick work really well. When it's too old either the flux evaporates or the copper oxidizes but a dip in liquid flux brings it right back.

author: Ian.M
author_rank: Super Contributor
timestamp: October 17, 2020, 05:38:13 pm
content: Yep. I suggested filing one of the needle bits to a bare copper hoof earlier. Put the 'firestick' on a light dimmer, powder some of the rosin and mix it with high % alcohol to get liquid flux, and soldering with it will go an order of magnitude more easily. However its a PITA having to keep adjusting the dimmer for the work, and for standby, and also a PITA to keep a bare copper bit dressed, so a good temperature controlled iron with a high quality plated hoof bit will be another order of magnitude easier to use and care for.Solderwick is very sensitive to surface tarnish. If you buy a large reel, wind it off onto a small spool to use it, without touching the braid with your skin and keep the main reel tightly wrapped in a bag. Don't buy more than you can reasonably use in a couple of years as unlike solder it doesn't keep well.If you dip it in good liquid flux, even the braid stripped off scrap cheap RF coax cable works as wick if its thin enough wires, and isn't tarnished. I don't recommend it as its less effective than a finer weave and usually too heavy for most work, but its worth remembering if you ever need to remove a lot of solder from a long joint, (e.g large fully soldered screening cans), and are running low on Chemtronics or other leading brand wick.

author: cigmas
author_rank: Regular Contributor
timestamp: October 27, 2020, 08:09:45 am
content: The Miniware TS100 arrived and already saw its first job. In short I love it. My soldering skill is now the weakest link in the chain.The BC2 tip's small but bevelled shape is such a relief to use. The light weight and small size make it easy to manipulate, and that's even with the the balance ruined by a big ferrite core on the (19V) power supply from an old laptop. If I were to use it very regularly I'd want to make an extension to the iron. The rapid in-tip heating and temperature regulation, the ability to turn it off easily between job stages, and its sleep feature, make me more likely to use it. I really like seeing the temperature to confirm when it's ready; it's surprising how quick it is.The first job was a repair on a TI-83+ calculator. Those wires are tiny ~2cm solid copper from telephone wire. The picture shows some ugliness but I could not see that much detail while working on it, given the small size and light reflections. The iron was at 320C and nearly instantly (<1s) melted solder on the tiny pads and wires. I would have like to make it prettier, avoid the occasional solder spikes and the nearly bridged 8th wire from the left, but decided not to mess with it too much after confirming with a multimeter that there were no shorts. No singed or lifted pads. I pre-tinned (+ flux only from the rosin core) every pad and wire and then joined them fairly easily, with positioning the wires being the biggest challenge. If I had to redo it, I would have left more insulation, but it would be strange to strip only ~2mm.Most importantly, the repair worked and the calculator is revived. The soldering was actually kind of fun instead of frustrating. I dread the thought of trying this job with the old iron/tip.After some use, the tip's metal got a bit browned all the way to the middle of the larger cylindrical part. I left a perhaps overzealous amount of solder blobbed on the tip to preserve it. Solder wets it very easily. The rosin from the solder core does leave dark brown deposits on the tip, which don't come off easily on the metal sponge while in use (and I don't spend too much time on it then), but after the tip cools the deposits get scraped off fairly easily in the brass.The image makes it looks patchier and rougher than it does to my eyes.As a post-analysis of the previous frustrations, and aside from tip issues, I think the metal sponge was/is dirty. I cleaned it a bit by getting as much of the old blobs out of it as I could. Using clean unused parts works nicely, but there is still a lot of solder on many strands and if those parts are used, solder bits and spikes get stuck on the new iron tip too.As for the solid rosin, I'm not trying to use it directly anymore. It works pretty well with indirect heating, i.e. heating a wick or wire in contact with the rosin. Even then, the rosin boils and smokes almost instantly. Wikipedia says rosin's boiling temperature is 100-120C. Now that I have an adjustable iron I might try a temperature closer to that range when dealing with rosin and maybe it will smoke less. I'm guessing the dark brown deposits are soot.

author: Psi
author_rank: Super Contributor
timestamp: October 27, 2020, 08:16:25 am
content: The trick is too avoid whatever you were using previously that was causing the problem. Without knowing for sure what that was.There could be chemicals on your brass coiled wire cleaner from the old iron that you don't want to get on the new one etc..When everything is working correctly no scraping is ever needed, just a casual push in and out of the tip in the coiled wire cleaner every so often.

author: cigmas
author_rank: Regular Contributor
timestamp: October 27, 2020, 08:29:10 am
content: Hmm good point about possible contamination. I might have to a new coiled wire cleaner sooner rather than later.

author: thinkfat
author_rank: Unknown
timestamp: October 27, 2020, 08:38:56 am
content: Tin whiskers are a sign of too little flux. Get a flux pen or some gel flux, this will take your soldering to the next level

author: Ian.M
author_rank: Super Contributor
timestamp: October 27, 2020, 09:48:08 am
content: The wire you used for your calculator repair is far to heavy for that sort of repair work. Except when the wires will be carrying a high current, as a rough rule of thumb, stranded wire should have a diameter of no more than two thirds of the width of the pad or track you are soldering to, and solid core wire, half the width, to allow enough space either side of the wire for a properly shaped solder fillet to form, and also so the wire is flexible enough not to excessively strain the bonding of the pad or track to the PCB substrate.To get fine wire suitable for repair work, if you want stranded wire, I suggest splitting up a ribbon cable - the 80 way PATA EIDE era cables are particularly fine. N.B as many ribbon cables were never intended to be soldered (always used with IDC connectors) their insulation tends to retreat rapidly at soldering temperatures. Strip and pre-tin the ends and trim to length *AFTER* tinning, then tin the pad and solder the prepared end to the pad quickly to minimise further insulation retreat.For solid wire, for bridging short gaps one can use bare strands taken from a larger cable, which should ideally be made from tinned wire so you don't have to faff around trying to evenly tin the strands before use.For longer insulated interconnects in solid wire, one can use magnet wire with solder-through polyester or polyurethane insulation, of an appropriate gauge, (though you need to pre-tin the ends as soldering through the insulation requires a higher temperature for far longer than is good to use on a PCB pad or track). Regular magnet wire insulation cannot be soldered through, and can be extremely difficult to remove without damaging the wire.For a solid wire that's easier to work with than magnet wire, I strongly recommend buying 30 AWG Kynar insulated, tinned or silver plated solid core wire-wrap wire, which, although wire-wrapping is rarely used as a construction method nowadays, is still readily available from all major distributors, Amazon, and EBAY, as its the preferred patch wire for signal circuit boards. Google:30 AWG wire-wrap wire

author: tooki
author_rank: Super Contributor
timestamp: October 27, 2020, 11:18:34 am
content: Quote from: thinkfat on October 27, 2020, 08:38:56 amJust to be clear, you are not talking about tin whiskers. (In English, other than in the verb “tinning”, as in a tip or wire, we do not use the word “tin” in electronics soldering for anything than referring to the element Sn. We never say “soldering tin” like in many languages.) “Tin whiskers” are the specific phenomenon of tin (again, Sn, not solder) growing needle-like crystals over time (on the order of years).I think you’re referring to either spider webbing or of the overheated joint, which then gets lumpy and forms spikes (sometimes called “solder dags”). (At my workplace here in CH, we call them “Hörnli”, little horns :p).

author: tooki
author_rank: Super Contributor
timestamp: October 27, 2020, 12:01:31 pm
content: Quote from: cigmas on October 17, 2020, 03:08:36 amBut youhavegotten fairly detailed explanations on each point.A skilled solderer could perhaps overcome one of those issues at a time. But not all of them at once: poor supplies, poor tool, excessive temperature.And while a novice with zero knowledge and zero intuition might not produce good work with a quality station, they’d be very unlikely to damage it (other than overcooking tips by keeping them too hot for too long without being sufficiently tinned).You’ve watched the Pace videos: knowledge-wise you’re now ahead of the vast majority of even experienced solderers. So you’re not going to ruin any equipment.Quote from: cigmas on October 17, 2020, 03:08:36 amNo you’re not! You’ve gotten lots of light in the thread!Quote from: cigmas on October 17, 2020, 03:08:36 amWell, proper soldering instruction is part of an electronics technician curriculum. But that’s just the basics. Beyond that, companies send their techs to get IPC certifications. But a lot of people are self-taught and never learned how to do it right. (And then, inexplicably, those folks all decide to go on YouTube and make soldering tutorials that get everything wrong....)I was never bad at soldering (especially once I got a real temperature-controlled station with good tip shapes; I can’t stand pencil tips), but the Pace videos (which I first watched maybe 3 years ago) took it to another level, thanks to providing the information to truly understand the process. By the time I began my electronics technician training (which I’m doing now), I was already soldering better than most of the 4th-year apprentices. (I just had a test on this, and got a top grade on it, they said the soldering was perfect.)The other thing is to practice, practice, practice the correct techniques. Do it with practice boards and junk boards you don’t care about — you WILL damage some boards and components while learning, and you don’t want to ruin a device you really wanted to repair.Quote from: cigmas on October 27, 2020, 08:09:45 amThat’s not strange at all. Wires need to be stripped to the correct length for the termination in question.As for solder spikes: they’re the symptom of a few possible causes: overheating a joint (as in, keeping it hot too long, resulting in oxidation, as well as increased contamination as the solder joint substrates dissolve into the solder, creating a mystery alloy with unpredictable properties), using too little flux, or of too low a temperature. (Too high a temperature increases the speed of oxidation. And if you ever see the oxide layer on the solder start to turn colors, you know it’s been way too hot for way too long.) With practice, you’ll be able to get in and out quickly. To fix a spiky joint, sometimes reflowing with flux is enough. But if it’s too contaminated, you want to desolder it, removing all the old solder, and start anew.Quote from: cigmas on October 27, 2020, 08:09:45 amCongrats on the successful repair. Satisfying, isn’t it?!For what it’s worth, I agree with the feedback about the wire used. Ian.M’s advice on this is absolutely perfect and thorough. Your thick wires are going to place a lot of strain on the pads, running a very real risk of them peeling off at some point.Your statement in bold ispreciselywhy I advise against using poor tools and supplies, and thus precisely why I said to replace the junk. You’ve now got the good iron, now pair it with good supplies!Quote from: cigmas on October 27, 2020, 08:09:45 amThere is absolutely nothing wrong with leaving a big blob of solder on the tip when you’re not making joints. I routinely melt some fresh solder onto the tip right after turning off the station, to leave a generous blob. The brown deposits sound normal. You can use a brass or fiberglass brush to remove the deposits instead of the brass wool.Quote from: cigmas on October 27, 2020, 08:09:45 amRosin blocks make no sense for electronics, as others have explained. Just buy some real flux. I’ve already given suggestions for affordable types.

author: tggzzz
author_rank: Super Contributor
timestamp: October 27, 2020, 12:09:34 pm
content: Quote from: tooki on October 27, 2020, 12:01:31 pmActually it has been extremely well explained by Dunning and Kruger, to the extent that the effect is known by their names(Context snipped, since that is averygeneral point)

author: tooki
author_rank: Super Contributor
timestamp: October 27, 2020, 06:03:48 pm
content: Quote from: tggzzz on October 27, 2020, 12:09:34 pmOh yes, I am well familiar with said syndrome (in others). What’s odd is why, it seems to me, soldering is such an unusually popular target of low-skill tutorials.

author: james_s
author_rank: Super Contributor
timestamp: October 27, 2020, 07:41:27 pm
content: Quote from: tooki on October 27, 2020, 06:03:48 pmProbably because it's one of the most basic skills that anyone dipping their toes into electronics is going to learn, I mean I was soldering before I was even 10 years old, back before I had a multimeter (they were expensive then). Being one of the first new skills learned it's only natural that there are a bunch of noobs who know just enough to feel like they know a lot and are eager to share their new skills.

author: tggzzz
author_rank: Super Contributor
timestamp: October 27, 2020, 07:43:38 pm
content: Quote from: tooki on October 27, 2020, 06:03:48 pmHmmm. Interesting question, worth some random poorly-expressed speculation."Users" don't solder, but "experts" do solder. Even monkey-see-monkey-do repairs often require soldering, and even atrocious soldering can work.People that think videos are wonderful things will want to rush in and make one. How better to do that than by showing to the world that you are no longer a mere user.Videos of soldering do actually add something over text, it is an easy subject to video, and cameras and distribution channels are too easily available.Add all that together and yootoob is the result.But those points can apply to many other disciplines, e.g. car mechanics, woodworking, etc. So, what are the equivalent videos there?

author: Shock
author_rank: Super Contributor
timestamp: October 27, 2020, 10:36:41 pm
content: To put it into perspective that is a professional job by some peoples standards that charge for repairs.Soldering is fairly easy after you learn the fundamentals, but it's not obvious so most people end up being rubbish at it. Good soldering is the hallmark of a skilled electronics enthusiast (I have a book that says this so it must be true).Get some decent consumables and you should be set, that tip looks like it's working better for you and tinning properly.

author: cigmas
author_rank: Regular Contributor
timestamp: October 28, 2020, 03:39:00 am
content: Quote from: Ian.M on October 27, 2020, 09:48:08 amQuote from: tooki on October 27, 2020, 12:01:31 pmYes I was worried about this and tried to bend the wires enough, but no doubt there is still some tension. Those wires were the thinnest I found on hand while still being strong enough to strip the insulation. Stripping stranded telephone wires almost always results in several lost strands. And that's with me carefully using the not-recommended pocket knife method (you can see I got impatient doing it 34 times and left some marks). Wire strippers/crimpers tend to absolutely butcher the poor things. I'm sure there are fancy wire strippers that perform well, but for now my pocket knife+patience beats everything else I've tried.The calculator wasn't even mine originally. I just saved it from being discarded. Economically, many of these repairs are not worth the time spent on them. It's driven by a dislike of waste and wanting to figure out how things work. I don't feel like finding new wires, stripping them, and redoing the repair, but now it will constantly be on the back of my mind. At least if it breaks I know where to look, though detached pads would be a bigger headache..Thanks again for the detailed suggestions and explanations. In the future I could try IDE cables if available, though it sounds like a bit of a pain. I thought of using copper strands from an old transformer lying around, but it seems too thin and many sections have worn insulation and corrosion:https://www.eevblog.com/forum/projects/ideas-for-what-to-do-with-old-transformers/msg3297848/#msg3297848Quote from: thinkfat on October 27, 2020, 08:38:56 amQuote from: tooki on October 27, 2020, 12:01:31 pmFlux looks like the next priority item. I looked for the suggested Stannol #165018 but availability to Canada and prices are not so good (~$25 CAD for 50ml). I'm thinking a no clean, non-corrosive, and non-conductive residue flux would be more practical for general use?Thoughts on Kester "44" resin core solder? (Sn 60, core 50, diameter 0.040") I spotted a local listing for an antique 5 lbs spool of it with probably enough remaining for a few lifetimes of hobby use.From the data sheet:https://www.kester.com/DesktopModules/Bring2mind/DMX/Download.aspx?Command=Core_Download&EntryId=1072&language=en-US&PortalId=0&TabId=96QuoteInteresting and somewhat confusing.

author: james_s
author_rank: Super Contributor
timestamp: October 28, 2020, 06:33:33 am
content: I rarely use flux other than what is in the solder. The exception is some surface mount assembly and reword. I have two different fluxes that I use, one is a regular rosin type and the other is a water based flux. I don't like no-clean fluxes because leaving the flux often looks ugly and I've found them harder to clean off than regular flux. The water based stuff is super easy to work with as it just rinses right of with warm soapy water but it's conductive so you HAVE to wash it off.

author: thinkfat
author_rank: Unknown
timestamp: October 28, 2020, 07:41:18 am
content: My next acquisition will be a small ultrasonic cleaner. I rarely work on PCBs larger than 100x100 millimeters, I'm guessing even a small jewelry-type cleaner will do, provided I use proper cleaning solvent.

author: cigmas
author_rank: Regular Contributor
timestamp: October 28, 2020, 08:16:18 pm
content: Quote from: james_s on October 28, 2020, 06:33:33 amLooks aside, I've heard some say they like leaving the rosin on, since it's an insulator. Maybe it can prevent some shorts and also stop or reduce oxidation.I also found a local listing for Kester 24-6337-6403https://www.kester.com/DesktopModules/Bring2mind/DMX/Download.aspx?Command=Core_Download&EntryId=1051&language=en-US&PortalId=0&TabId=96QuoteBut the cleaning requirements make it seem like a hassle. eg. I don't know how I would clean it off the calculator job under and behind those tiny wires. Seems to complicate the issue.Quote from: thinkfat on October 28, 2020, 07:41:18 amAh, maybe that's one way.

author: wizard69
author_rank: Super Contributor
timestamp: October 29, 2020, 08:50:42 am
content: Quote from: cigmas on October 12, 2020, 11:12:43 pmYou really need to know what you are working with. You could easily be using plumbing solder with high corrosive flux. If plumbing solder purchased recently, it could be lead free which has its own soldering issues. You could also have lead free electronics solder which again solders differently than 60/40. beyond electronics and plumbing, there are other solders out there.So I'd make a point to buy some quality solder for your new iron. Keep it identified as to alloy and flux core.

author: james_s
author_rank: Super Contributor
timestamp: October 29, 2020, 09:42:07 pm
content: Even top quality name brand solder of known composition is not very expensive. A 1lb roll typically lasts me around a decade, and smaller rolls are available if money is tight or you don't know exactly what you want.

author: uli12us
author_rank: Contributor
timestamp: November 01, 2020, 06:09:25 pm
content: Flux is an important part, Actually, I use only a selfmade flux since many years, that is in Alkohol or IPA soluted Kolophonium. I took a nail-enamel bottle, fill it with kolophonium up to 1/2 and fill it complete with alcohol. After a day or so, you get a liquid whose looks like tea, whose can simply brush on the object, with the small brush in the cap. I often read that the NC-559 from AMT should be a good flux for reflow soldering, maybe I should buy a small amount for special parts. But I don't know if its useable for Sn-Pb solder. Maybe it needs the higher temperatures from the leadfree solder.

author: Shock
author_rank: Super Contributor
timestamp: November 02, 2020, 04:21:16 am
content: Quote from: uli12us on November 01, 2020, 06:09:25 pmNC-559-V2-TF is optimized for Sn-Pb. It's ROL0 classed flux so rosin based low activity and aside from that it's also "no clean", so should have minimal residue conductivity but you will be cleaning it anyway. There is a NC-559-ASM-TF which I believe is a higher temp version and NC-560-LF-TF which is the lead free version, both also ROL0 classed.

author: cigmas
author_rank: Regular Contributor
timestamp: November 02, 2020, 06:28:30 am
content: Looking at local electonics specialty stores, they don't have too many options for flux and several of them are the cheap stuff found on the Chinese sites, such as the Pro'sKit 8S005 flux paste. They even sell the same solid rosin I have.But they also have other brand name fluxes like MG Chemicals 835 liquid flux, and another branded paste flux apparently the same as Kester SP-44.Looking at the 835's data sheet I learned something confusing: apparently non-conductive, non-corrosive residue does NOT mean no clean? I thought those properties were what made it 'no clean'.QuoteQuotehttps://www.mgchemicals.com/downloads/tds/tds-835-l.pdfSimilarly with solder, the shops don't necessarily advertise the brand or flux specifications (other than "rosin") of the solder, just the diameter and lead alloy ratio (60/40 or 63/37), and sometimes the core %. Conveniently they also sell small quantities for a low absolute price which should be good for hobbyists who don't need much.Quote from: uli12us on November 01, 2020, 06:09:25 pmThanks for sharing your recipe. How is the smoking and residue? I assume you used 99% or higher IPA?Any preference between paste or liquid flux? Dropper or brush applicator?

author: helius
author_rank: Super Contributor
timestamp: November 02, 2020, 07:04:26 am
content: Rosin based flux should normally be non-conductive and non-corrosive. Therefore, it doesn't usually need to be cleaned, but because it is a dirty brown deposit, it looks more professional if you do clean it. No-Clean is specifically a concept to bypass the need for cleaning in production shops, so the brown deposit wouldn't fly. They are instead made to leave a thin clear deposit: one of the side-effects is that the deposit won't dissolve well in alcohol. No-Clean is usually low-solids which means less fluxing activity, although many different definitions of "No-Clean" are in use commercially. Being low solids makes it not very suitable for rework where oxide contamination is often present.The only type of  flux that really can't be left in place is water soluble or ORganic flux. The residues are conductive and corrosive and should be washed off in warm water.

author: Electro Fan
author_rank: Super Contributor
timestamp: November 02, 2020, 07:16:45 am
content: Quote from: cigmas on November 02, 2020, 06:28:30 amLiquid is a spill waiting to happen. I’d start with a (~medium thick felt-ish) pen and see how that goes. I’ve had good luck with MG Chemicals. Press down a little and it is somewhat controllable as it dispenses.

author: Shock
author_rank: Super Contributor
timestamp: November 02, 2020, 09:18:52 am
content: Nothing wrong with liquid flux. You can use a flux pen (they have refillable ones) or as mentioned above a varnish bottle if you want a brush applicator. A small plastic bottle with needle applicator works. For paste/tacky flux syringes work well or you can use a toothpick or cotton bud with the end chopped off etc.

author: tooki
author_rank: Super Contributor
timestamp: November 02, 2020, 11:34:40 am
content: Quote from: helius on November 02, 2020, 07:04:26 amUnfortunately, that’s only entirely true in fully controlled processes like reflow soldering. Many (most?) no-clean fluxes must reach soldering temperature to fully neutralize, and in hand soldering, that’s often not the case.I’m running an experiment right now with all the fluxes i have at home and work, for tinning wire. I took each flux and applies it on two stranded copper wires. One each was then tinned, the other was left unheated to see how corrosive it is.Only one flux (an old radio shack rosin flux gel) is corrosive before heating.The no-clean fluxes cause no corrosion when unheated. But when partially heated (as with the flux that wicks under the insulation), they become corrosive. The fully-heated area is not corrosive.So clearly, there’s a minimum temperature that must be reached to activate the flux, but also another, higher temperature that must be reached to neutralize it again. If the highest temperature reached isbetweenthose two, the flux remains in a damaging corrosive state.Additionally, many no-clean fluxes are exceedingly hard to remove with IPA, leaving tons of potentially corrosive or conductive salts. Commercial flux removers do a good job though.

author: cigmas
author_rank: Regular Contributor
timestamp: November 02, 2020, 08:44:10 pm
content: Apparently "just get some decent flux" isn't a trivial matter after all.The more I read the more confused I get. For example, the MG Chemicals 835 liquid flux says non-corrosive and non-conductive but does not say no clean, the data sheet instructs to clean it off and not just for aesthetic reasons, plus an MG Chemicals employee answered a question on Amazon on this very question of whether it is no clean:Quotehttps://www.amazon.ca/ask/questions/Tx1O22UPFK4LCI5/A forum post on another site by someone researching fluxes:Quotehttps://forums.qrz.com/index.php?threads/solder-fluxes.575825/So some additional things to consider: the environmental condition of the application, the temperature to which the non-consumed flux will be exposed, whether the flux residue was charred... Is anyone's head *not* spinning yet?Regarding flux pens, for some reason they are 10X more expensive. Eg. local shops price the 10 mL 835 liquid pen at nearly the same price as the 125 mL bottle. That doesn't sit well with me. Plus some complain that flux pens can be unreliable and suddenly release too much liquid.What about using a smaller bottle with a dropper? Would flux get gummed up in the dropper?

author: Electro Fan
author_rank: Super Contributor
timestamp: November 02, 2020, 09:22:53 pm
content: Quote from: cigmas on November 02, 2020, 08:44:10 pmFlux might right up there with crimper connectors and other stuff in the "how hard can it be to figure out?" category of things that start out seemingly simple and trivial.And everything liquid in a bottle is waiting to spill; small bottles just spill less.

author: james_s
author_rank: Super Contributor
timestamp: November 02, 2020, 11:05:37 pm
content: Quote from: cigmas on October 28, 2020, 08:16:18 pmMaybe so, but back when CRTs were king I worked on quite a few where leftover flux had absorbed moisture over time and either caused carbon tracking on the PCB, or issues with the focus, screen grid and other relatively high voltage areas. There was one model of 14" or 15" VGA monitors in particular where I remember flux would turn conductive and short out the G2 pin on the neck board resulting in dim or no picture.

author: tooki
author_rank: Super Contributor
timestamp: November 02, 2020, 11:20:49 pm
content: Quote from: cigmas on November 02, 2020, 08:44:10 pmUmmm, the pen-style dispensers are comparatively expensive. (Bottles cost next to nothing.) Most of the price of the flux pen is the pen itself, as evidenced by the cost of empty pens, which are available for people who want to decant a rarer flux type into a pen. But they’re also not intended to be disposable — most flux pens are meant to be refilled, and even replacement nibs are readily available. So you refill them with inexpensive liquid flux and replace the nib if you feel it’s worn out.Quote from: cigmas on November 02, 2020, 08:44:10 pmYou need to press lightly, not jab at it.

author: Shock
author_rank: Super Contributor
timestamp: November 03, 2020, 12:00:14 am
content: It doesn't need to get too complicated. Most people will be fine to start off with a rosin core Sn/Pb solder wire and a liquid, paste or tacky flux (ROL0 is rosin based low activity and halide free). Optionally you can use a lead free wire and compatible flux which can also be ROL0. Reading the datasheet and safety datasheet will cover process, cleaning and safety concerns.So unless you're hunting for some magic formula, it's fairly simple. Decide on the solder alloy, the flux core and then use an external flux to match the wire. Then your process for cleaning is similar, there is just more of the same residue on the board. If you want to use the same type of flux but a more active version you can.Edit:If you get bored you can read something like thishttps://www.pillarhouse.co.uk/wp-content/uploads/301-Choosing-a-Flux-11-2016.pdf

author: uli12us
author_rank: Contributor
timestamp: November 03, 2020, 01:29:53 am
content: cigmas @ Yesterday at 06:28:30 am; Thats a good point, for electronics, always use 99% up alkohol, IPA, the soluted 70% or so are only good for desinfectant. If you use it, it spits, because the rosin isn't water soluble. I don't like the "modern" water soluble fluxes. They are good for the industry, because cleaning the boards is easy, but not for an electronic tinkerer. If you put away a roll of such solder, than water will sucked from the core and it spits.And I think, my liquid flux smells not different from a rosin based solder, no wonder, the flux is the same, not exactly, but the base is the same.

author: cigmas
author_rank: Regular Contributor
timestamp: November 04, 2020, 05:20:21 am
content: Quote from: Electro Fan on November 02, 2020, 09:22:53 pmFunny you should mention that. I'm also in the middle of a repair involving crimp connectors and was confused on that front as well.Quote from: tooki on November 02, 2020, 11:20:49 pmOh I see. This was not obvious to me at all.Quote from: Shock on November 03, 2020, 12:00:14 amExtensive reading seems to be the only way to get a handle on this topic. It appears to me that "no clean" is almost more like a branding or type designation than an indication of not needing to clean residues. The necessity to clean seems dictated more by application/environmental conditions and process requirements.Many of the fluxes and solders I looked at are classified ROM1 or similar, even though they say non-conductive non-corrosive residues. I wonder how homemade rosin flux would be designated. Maybe it depends on the proportion of rosin used?Quote from: james_s on November 02, 2020, 11:05:37 pmPerhaps that is a high voltage environment that carries a stricter requirement for cleaning? In addition, some repair videos mention that some glues on PCBs turn conductive and cause shorts after degrading over time.Quote from: uli12us on November 03, 2020, 01:29:53 amGood to know. Yet another detail to watch out for. Water soluble fluxes sound like quite a hassle for general hobby use.-----All this is rather exhausting. I'm tempted to just get some 99(.9)% IPA which I need anyway, make my own dissolved rosin soup and see if it's good enough.

author: Shock
author_rank: Super Contributor
timestamp: November 04, 2020, 06:36:49 am
content: Quote from: cigmas on November 04, 2020, 05:20:21 amIt's "no clean" in quotes for that reason.Like I said in my last post it's not actually that complicated. Most hobbyists if unsure will pickup some 63/37 SnPb with rosin core and some ROL0 flux, can't really go wrong. The wire size you want to keep proportional to the pad/leads which allows for better flow control. If you want to learn the nuances (just like in any other topic) it's optional.Homemade rosin flux made from pure rosin would typically be ROL0 (low) or slightly more active depending on how the rosin source is refined/purified. Additives are deliberately used to increase the activity in medium/high classes of rosin flux.

author: james_s
author_rank: Super Contributor
timestamp: November 05, 2020, 01:37:30 am
content: I soldered for probably 15 years before I ever had any flux other than what is in the core of the solder. I only really started using flux when I started working with a lot of surface mount parts.

author: Electro Fan
author_rank: Super Contributor
timestamp: November 05, 2020, 03:54:37 am
content: Quote from: blueskull on November 05, 2020, 01:52:28 amWhy and how does it do that?

author: cigmas
author_rank: Regular Contributor
timestamp: November 05, 2020, 05:06:10 am
content: I got a TS100 with the BC2 tip and reused a 19V laptop power adapter, corresponding to up to 40W according to the manual. It keeps my total cost at about half that of the TS80P and avoids the confusing issues with USB power standards of the TS80. I quite like it.An EEVBlog overview of the TS80P:A really not-too-thorough, apples-to-oranges EEVBlog comparison of the TS100 vs TS80 which was removed but mirrored:There are more accurate reviews out there, but hey, we get to see the less flattering sides too.

author: cigmas
author_rank: Regular Contributor
timestamp: November 05, 2020, 05:38:48 am
content: Thanks for that helpful comparison.I don't have a power bank or fast charger (confusing array of choices there too), so all of that is extra cost and confusion for me. I am using the Ralim firmware for fun though.The only change I would make if I used the iron regularly would be to make a flexible and lightweight adapter between the iron and the DC plug. But for my occasional use, I'm not sure I'll bother with that (yet).How important is it for the iron to be grounded for typical hobbyist use? The TS100 has a grounding screw for a ground wire. I don't know if it gets ground via the power adapter. The PACE videos had mentioned potential issues if different ground references are used in the work area. It might be time for me to rewatch those lessons.

author: tooki
author_rank: Super Contributor
timestamp: November 05, 2020, 04:27:24 pm
content: Quote from: cigmas on November 05, 2020, 05:38:48 amIf you power it from the wall using a switch mode power supply like a phone charger, I would call grounding critical, as SMPSs use capacitors to reduce EMI, but these cause the supply to float at half of mains voltage, albeit at minuscule current. But for some components this is enough to zap them.

author: cigmas
author_rank: Regular Contributor
timestamp: November 05, 2020, 07:24:43 pm
content: What about laptop power supplies?

author: Ian.M
author_rank: Super Contributor
timestamp: November 05, 2020, 07:44:03 pm
content: I haven't seen a laptop PSU that wasn't switched mode since the era when laptops were the size of a large briefcase, were heavy enough to turn you into an asymmetric knuckle-dragger and if you were stinking rich, had an orange monochrome EGA plasma screen!If the laptop PSU has a two pin mains connector, its ungrounded and is unsuitable for soldering irons without extensive modification. If its got a three pin mains connector it *MAY* be grounded. If you can measure continuity from power in ground to DC out 0V it is grounded, and should be suitable. Unfortunately there are many Chinese fake PSUs with three pin connetors and recycled ungrounded 'guts'.

author: cigmas
author_rank: Regular Contributor
timestamp: November 05, 2020, 08:25:09 pm
content: The power supply is the original one that came with a laptop:Between the power supply's round ground input prong, I measured 1.3to the output's barrel (negative) contact, and 1.9 kto the center (positive) contact. There is no continuity to output from either of the flat (live, neutral) input prongs.

author: Gyro
author_rank: Super Contributor
timestamp: November 05, 2020, 08:33:00 pm
content: Yes, that's a suitable grounded output one (an original too rather than a cheap ebay 'replacement' one).

author: Ian.M
author_rank: Super Contributor
timestamp: November 05, 2020, 08:52:57 pm
content: Quote from: tooki on November 05, 2020, 04:27:24 pmYep. Here's the saga of many zapped 2N7000 MOSFETs due to a mains connector adapter with a defective (by design) ground pin used with a Hakko FX888D soldering station:https://www.eevblog.com/forum/beginners/simple-fet-circuit-for-onewire-protocol-doesn_t-work-as-expected/msg1277272/#msg1277272

author: cigmas
author_rank: Regular Contributor
timestamp: November 18, 2020, 12:51:06 am
content: I got the only flux paste carried by the electronics store I frequent, and also made a small (~5ml) batch of my own rosin/IPA liquid flux which I apply using a handy dropper. Both work ok, certainly better than no flux. The ProsKit sputters and sizzles a fair bit and leaves a clear residue but the paste consistency is often convenient, while my rosin liquid flux leaves a more visible yellow/brown residue. Both are pretty easy to clean with IPA, and I've been cleaning residues given the warning label even though I'm not using it on ICs or high voltage/power applications. I also found another electronics store with more variety for the next purchase, but for now these seem to do the trick.The wire sponge replacement I got has a couple of noticeable differences: the color is more yellow (brass-like) vs the old one's more reddish (copper-like) color, and the diameter of the turnings is less than half of the old one and more regularly arranged. I haven't used the new one yet while soldering, but I can tell it will be more pleasant to use because the smaller diameter turnings hug the tip much more closely and the arrangement makes it easier to poke the tip rather than the more difficult stabbing required in the more disorganized old sponge.I also got a desoldering pump, which already saw a bit of use. I find it quicker and less frustrating to use on large clumps of solder, which take longer to absorb using solder wick. Solder wick might do a better "finishing" job to get the last traces of solder when that is required.My technique can certainly use improvement, but at least the frustrations are gradually reducing.

author: Psi
author_rank: Super Contributor
timestamp: November 18, 2020, 07:25:16 am
content: Quote from: cigmas on November 18, 2020, 12:51:06 amDue to the warning I'm worried that flux might be acid flux.If it's acid flux then it's intended for pipes and metal work rather than anything electrical and will damage the coating on your iron tip pretty fast.EDIT: looks like it's not acid flux.

author: thinkfat
author_rank: Unknown
timestamp: November 18, 2020, 07:36:49 am
content: Quote from: Psi on November 18, 2020, 07:25:16 amReally? The warning label clearly says its corrosive. It says don't use for electronics and high voltage, so it's conductive. Conductivity comes from free ions and water, which together with the warning label tells me it's very likely acidic.

author: Psi
author_rank: Super Contributor
timestamp: November 18, 2020, 07:41:52 am
content: Quote from: thinkfat on November 18, 2020, 07:36:49 amI'm not saying it's safe to use, but I looked up the part number and it's not an acid flux.

author: Psi
author_rank: Super Contributor
timestamp: November 18, 2020, 07:45:12 am
content: Looks like it's a very aggressive non-acid flux.I wouldn't let this anywhere near my electronics or my iron tips.I'm getting conflicting info about it though, everywhere that's selling 8S005 has it called a "non-acid flux" in the title/name.But it contains zinc chloride which implies it's an acid flux. Although no actual acid listed in contentsbut I will differ to someone with more chemistry knowledge.Petrolatum 75%Zinc Chloride 15%Water 10%I have attached the MSDS

author: thinkfat
author_rank: Unknown
timestamp: November 18, 2020, 07:53:28 am
content: It spits:https://youtu.be/iKDAmY9Rdag?t=312And it's conductive even after cleaning with PCB cleaner:https://youtu.be/HBwvD4W40MMDon't use. It will only give you more frustration.PS: Wikipedia says about hydrated zinc chloride: It gives off highly reactive HCl (hydrogen chloride) when heated, so better not have your eyes and lungs exposed to the fumes.Watery solutions of zinc chloride are strongly acidic. pH of 1 for a 6M watery solution.

author: Psi
author_rank: Super Contributor
timestamp: November 18, 2020, 07:55:14 am
content: Yeah, I think we are all in agreement that the 8S005 flux should be kept well away from electronics and soldering iron tips.Even if it's not an acid flux, it definitely *is* a very aggressive and corrosive flux.So it will cause damage to your iron tips and destroy electronics over time.

author: Ian.M
author_rank: Super Contributor
timestamp: November 18, 2020, 09:28:42 am
content: Its an acid flux. Zinc chloride disproportionates, so if you've got free zinc chloride + even ambient humidity, you've got some hydrochloric acid present.Its certainly not fit for general electronics use, but may come in handy if you need to tin difficult metals like bare steel, provided you can clean the part with near-boiling water and soap (not detergent - you want the alkaline soap to neutralize any traces of acid) *BEFORE* soldering a wire to the freshly tinned patch using electronics grade flux.

author: cigmas
author_rank: Regular Contributor
timestamp: November 18, 2020, 08:54:08 pm
content: Well that's just dandy. Frustration inching up again. *sigh* How can the harmful residues be cleaned off of contacts and the iron tip? I could try hot soapy water, but who knows what else is in household soap bars, like fragrance, moisturizers, etc.This was literally the only flux paste in the electronics shop, and recommended by the worker there who said they used it for their soldering. However, they had no comment about the warning label when I pointed it out; it seemed like they had never even noticed it. At least I still have my rosin/IPA liquid flux.Also interesting to note that both Youtube videos linked previously show the ProsKit 8S005 flux being used for electronics and ICs, even if the latter was just for demonstration.

author: Renate
author_rank: Super Contributor
timestamp: November 18, 2020, 09:17:57 pm
content: I use a toothbrush and IPA. I would never use "no-clean".

author: Ian.M
author_rank: Super Contributor
timestamp: November 18, 2020, 09:46:34 pm
content: Fragrance and moisturizer additives in household soap will be *MUCH* easier to clean off your tip than Zinc chloride residue! However if you have any real soap flakes (not detergent) or a bar of laundry soap handy, they typically don't have much/many additives.

author: tooki
author_rank: Super Contributor
timestamp: November 18, 2020, 11:02:35 pm
content: Quote from: cigmas on November 18, 2020, 08:54:08 pmAnd this ispreciselywhy I told you to buyname-brandsupplies:Quote from: tooki on October 15, 2020, 05:41:36 pmI said that not to be sanctimonious or elitist, but to spare you the frustration of dealing with crappy materials, which waste your time and money. If local shops don't carry the good stuff (which is the case practically 100% of the time), then do like everyone does and have it sent to you. There are good distributors for every last corner of the planet.Quote from: cigmas on November 18, 2020, 08:54:08 pmWell the second video was literally a demonstration of why it'snotsuitable for electronics.FYI, a flux like that is OK for coarser electrical work, like perhaps soldering solid (not stranded!!!!) wire to solder lugs. But I'd definitely clean it thoroughly.Don't worry about your iron tip too much: just clean it with lots of alcohol and you'll be fine. Use your old crappy brass wool to gently scrub off any encrusted flux that won't dissolve with solvent alone.

author: cigmas
author_rank: Regular Contributor
timestamp: November 19, 2020, 12:48:50 am
content: Quote from: Ian.M on November 18, 2020, 09:46:34 pmI found a bar of Sunlight "Pure Soap" in the laundry room. Will this do?Ingredients: SODIUM TALLOWGATE, AQUA, SODIUM COCOATE, GLYCERIN, PARFUM, SODIUM CHLORIDE, CITRIC ACID, TETRASODIUM EDTA, SODIUM SILICATE, CI 77891, ETIDRONIC ACID, CI 11680, BHTQuote from: tooki on November 18, 2020, 11:02:35 pmI don't see visible residue, at least not from the S8005. Rosin flux leaves brown residues which come off fairly easily with IPA, and the brass wool scrubs it off relatively easily as well if it comes in contact. I didn't used IPA or anything else to clean the tip (yet), just solder and scrubbing in the wool after use.Quote from: tooki on November 18, 2020, 11:02:35 pmThat Stannol 165018 is hard to find for me at any reasonable price. And online orders, particularly shipping, have gotten more expensive compared to shopping locally in many cases.MG Chemicals products seem more easily available. I see one shop has the 8342-50G flux paste listed for what seems a slightly pricey $11https://www.mgchemicals.com/products/soldering-supplies/soldering-flux/ra-rosin-flux-paste/Another store carries only a home brand 50g paste which has the same dark brown color but virtually no information available.. but at 1/3 the cost. Maybe I'll find more options as I keep searching.

author: helius
author_rank: Super Contributor
timestamp: November 19, 2020, 02:41:26 am
content: That "same brown color" can easily be a plumber's flux with zinc chloride. Don't use anything on electronics that isn't labeled for such use.

author: Psi
author_rank: Super Contributor
timestamp: November 19, 2020, 07:07:12 am
content: Quote from: Ian.M on November 18, 2020, 09:28:42 amHow come every listing for it says acid-free flux in the title?

author: thinkfat
author_rank: Unknown
timestamp: November 19, 2020, 09:40:17 am
content: Quote from: Psi on November 19, 2020, 07:07:12 amYou wanted opinion from someone with more experience in chemistry, right? :-)

author: tooki
author_rank: Super Contributor
timestamp: November 19, 2020, 05:53:35 pm
content: Quote from: cigmas on November 19, 2020, 12:48:50 amWhat country do you live in? (You should set this in your profile so people already know when asking for product advice.)

author: james_s
author_rank: Super Contributor
timestamp: November 19, 2020, 07:17:30 pm
content: I don't understand why this is going around in circles for so long. You don't even need flux, there are reasons to have it but if you are learning to solder all you need is an iron and a roll of rosin core solder, that's it. You can do almost all soldering without using any additional flux, and you should be proficient at basic soldering before you even worry about flux. Practice the basics and then work on more advanced techniques once making a nice clean solder joint on a through-hole component is second nature.

author: cigmas
author_rank: Regular Contributor
timestamp: November 19, 2020, 09:51:41 pm
content: Quote from: helius on November 19, 2020, 02:41:26 amIt looked to have a similar non-homogeneous texture and hard consistency as images of the MG Chemicals 8342. I spoke to several employees of that store and nobody seems knows what it is other than "it works and they sell tons". They seemed annoyed by me asking for technical data sheets or MSDS. Oh, and btw it is labelled "solder paste" when it is clearly not solder, while it makes no mention of flux. That prompted them to say they couldn't keep talking to me.Quote from: tooki on November 19, 2020, 05:53:35 pmCanadaQuote from: james_s on November 19, 2020, 07:17:30 pmFor soldering, sure, but this thread started mainly because of difficulty in de-soldering, with the de-soldering braid not wicking solder, and flux helped with that.

author: nukie
author_rank: Frequent Contributor
timestamp: November 20, 2020, 06:41:07 am
content: In regards to the Chinese rectangular solid crystal flux in the original post, it's a popular flux but not for actual soldering.It is used with a hot solder tip to produce lots of smoke with white flux residue. While smouldering the solder tip is placed closed to IC components so they are coated with a layer of white flux residue. Next power applied to the circuit board suspected of short circuit. The component that is hot will melt the white flux residue.A cheap way to detect shorts rather than a thermal camera.

author: Psi
author_rank: Super Contributor
timestamp: November 20, 2020, 10:38:08 am
content: Quote from: thinkfat on November 19, 2020, 09:40:17 amSorry, I wasn't questioning Ian.M post. but it kind of seemed like I was.I was more wondering if there are multiple types of acid flux where some contain actual acid while others only produce acid when heated. Maybe the non-acid title refers to it not being the type of flux that contains acid in its supplied form?And if so, where are the names for these two types of flux. Flux that has acid or flux which produces it when heated.

author: cigmas
author_rank: Regular Contributor
timestamp: November 20, 2020, 08:32:30 pm
content: Quote from: nukie on November 20, 2020, 06:41:07 amThat's neat, but other than the white-ish smoke/vapor I haven't noticed white residue on the board or components. What is the name of the compound used for short detection?=====I cleaned the iron tip and board with warm soapy water and scrubbed with a cotton swab and a brush, rinsed with demineralized water and later IPA. Hopefully that heads off any potential issues.An odd observation is that the concoction I used turned into a strange slimy consistency. The preparation was made with shavings from the Sunlight "Pure Soap" bar in a small styrofoam cup, to which some warm water was added, and stirred with a cotton swab. At first I thought the cotton tip was just expanding in the liquid, but then realized a slime was developing on or from it. After about a couple of hours, the entire "soapy" liquid was a single coagulated blob of viscous slime. I wish I understood chemistry better.

author: uli12us
author_rank: Contributor
timestamp: November 21, 2020, 09:06:55 am
content: I can't understand you, You have bought a really good soldering iron and made yourself a simple but useful rosin based Flux. After that you buy a flux, thats only good for water- and rainpipes.In School we use such a flux for soldering steel sheets together with a gas heated Solder hammer.For other usings ists completely useless. I have said before, the NC-559 from amt should be a really good flux for Electronics, the simplest china fake of it, its much better than a roofers Flux like that.But better you buy the original.

author: Ian.M
author_rank: Super Contributor
timestamp: November 21, 2020, 02:03:27 pm
content: Quote from: cigmas on November 20, 2020, 08:32:30 pmCleaning followed by thorough rinsing with water then pure alcohol generally alleviates most surface contamination issues.I suspect the 'slime' is simply due to an insoluble soap, a mixture of mostly zinc tallowate, and some zinc cocoate, thickening the soap solution. Metal salt soaps apart from those of the alkali metals typically have low solubility.If you have the time, a little experimentation could provides some further clues to the cause of the slime. Prepare another batch of soap shavings in warm water in a well-cleaned jam jar, and tip a quarter each into two styrofoam cups and another jar. Put a cotton tip each into one of the cups and one of the jars. If none of them coagulate, its probably due to zinc ions from the board forming a zinc soap, otherwise you will be able to determine if its related to the cotton tips (maybe adhesive binding the cotton to the stalk) or the styrofoam cups.Repeating the experiment in the second video for yourself with as many different fluxes as you have handy using small scraps of matrix board as samples, and trying various methods of cleaning them using various solvents may also be educational. For comparison as controls, clean an unsoldered sample with alcohol, another with alcohol then soak it in distilled water, and another in just distilled water. The low resistance is likely to increase as the samples dry, so take readings hourly for a couple of hours, then four hourly, then 12 hourly, then daily until you are sure the resistance has stabilised.

author: tooki
author_rank: Super Contributor
timestamp: November 21, 2020, 05:07:49 pm
content: Quote from: cigmas on November 19, 2020, 09:51:41 pmThe inconsistent use of the terms "soldering paste", "solder paste", "flux paste", etc. is highly irritating.But I think it's easy to explain: flux pastes predate the invention of solder paste (i.e. solder powder in flux paste). So back then, especially in non-electronics soldering, the term "solder paste" established itself as "that paste you smear on the copper (sheet, pipe, etc) before soldering it", hence "soldering paste", and then shortened to "solder paste". We know solid rosin has been used as a flux for millennia, so I wouldn't even be surprised if flux pastes have existed for centuries.Then SMD came along a few decades ago (in the 1960s), and with it, the need for modern solder paste. In the electronics world, the terms became fairly clear: "solder paste" means solder powder suspended in flux paste, and paste-form fluxes are called flux paste, flux gel, tacky flux, etc. depending on their appearance and consistency. But in the plumbing and sheet metal worlds, where solder-powder-in-flux isn't a thing, they never changed their terminology. If anything, it's become somewhat of a good indicator: if something says "solder paste" on it andisn'ta gray paste, you're practically guaranteed that it's not intended for electronics.Quote from: cigmas on November 19, 2020, 09:51:41 pmSo go to digikey.ca, mouser.ca, canada.newark.com, etc and buy yourself some proper supplies.For example, on digikey, you can get SRA Soldering Products FLS135 rosin flux paste, for CAD13, or Caig RSF-R39-2 for CAD19 (which looks like perhaps a smoother consistency) either of which whose datasheet expressly says it does not need to be cleaned off, and it'll last you a loooooong time. If you prefer a syringe, SRA's TF5000-30CC is CAD20 (it comes in smaller syringes too, but the savings are so small it's not worth it).Then get an reel of good solder, for example, either SRA's WBRC63/3732 or Chip-Quik's RASW.031 is just CAD38 on digikey, or if you want premium brands, CAD50-55 gets you Kester 24-6337-9713 or Multicore 386862, for example. (All are 1lb of 63/37, RA or RMA flux, 0.8mm.)Also consider getting a flux pen and some high-quality solder wick (I recommend MG Chemicals, which has a finer braiding than any other I've seen).It's worth the investment, and this stuff will last you a long time. I'm still on the lb roll of Kester solder I bought 5 or 6 years ago and I'm not even close to finishing it.

author: Electro Fan
author_rank: Super Contributor
timestamp: November 21, 2020, 09:43:54 pm
content: https://www.all-spec.com/Product/24-6337-9713-16600Not sure if All-Spec sells in Canada but they are reliable with good prices on Kester.

author: tooki
author_rank: Super Contributor
timestamp: November 21, 2020, 09:59:56 pm
content: Quote from: Electro Fan on November 21, 2020, 09:43:54 pmThose are great prices indeed.20 seconds of navigating to the page footer, clicking on “shipping”, and scrolling down provided this:QuoteSo I’d take that as a “probably not” for a home user, especially one as defeatist as the OP.

author: Electro Fan
author_rank: Super Contributor
timestamp: November 21, 2020, 11:09:56 pm
content: I think credit cards are a thing in Canada.Take 3-5 min, put the order in, see if it’s accepted.Or call them on the phone.

author: uli12us
author_rank: Contributor
timestamp: November 23, 2020, 12:42:09 pm
content: That is not a recommendation of this special flux, I have named before. At the moment I'm in search of a dealer they can ship the original for a good price. Only 3 simple examples from Ebay. There are several others who ship to canada. Many american sellers, but I don't know if they'll ship to canada.https://www.ebay.com/itm/4pcs-10ml-AMTECH-Flux-Type-NC-559-ASM-UV-BGA-PCB-Flux-Paste-SMT-Solder-Product/223738722538?hash=item3417ddf8ea:g:2zwAAOSwc1FXY6Rdhttps://www.ebay.com/itm/1PC-Amtech-BGA-NC-559-ASM-Flux-paste-ROHS-USA-made/392347793416?hash=item5b59c03808:g:BUwAAOxy4kpRASFchttps://www.ebay.ca/itm/100g-NC-559-ASM-BGA-PCB-SMT-IC-Reballing-Soldering-Hot-New-Flux-Paste-Greas-S3V9/303756193466?hash=item46b947aeba:g:X7AAAOSwMp9fpYnJBut I fear, the last 2 are fakes.Normally, the companys use Solder(ing) paste for compositions with metal they all have a gray colour, If the colour is yellow, green, white, brown or similar, than its only a flux without metal. The original NC-559 from AMTech contains metal in different alloys. The important part is the letters behind the Name. Some say its only flux. but at the moment I can't reach the server fromthe company. Unfortunately, the table with all the different codes is gone.Here you can read about the parametres and using of the different sort of fluxes, solder pastes and more.https://amtechdirect.com/category/amtech-tacky-solder-flux/

author: helius
author_rank: Super Contributor
timestamp: November 24, 2020, 04:41:27 am
content: Quote from: uli12us on November 23, 2020, 12:42:09 pmNC-559-TF (for "tacky flux") is the corresponding flux without solder spheres. Amtech uses the same naming convention for all their products, the flux-only variant contains '-TF'. There are sometimes different versions of the tacky flux (for instance, '-V2').

author: tooki
author_rank: Super Contributor
timestamp: November 24, 2020, 07:07:20 pm
content: Quote from: uli12us on November 23, 2020, 12:42:09 pmShenzhen? That makes me pretty certain the first one is fake too. You pretty much won’t find the genuine article on eBay.

author: james_s
author_rank: Super Contributor
timestamp: November 24, 2020, 10:45:42 pm
content: I got some flux on ebay that seems to be genuine, but it came from the US and was sold as expired, works fine. For someone who lacks the expertise to determine the quality of something like that I would definitely suggest buying the real deal from a reputable dealer to be 100% certain.

author: cigmas
author_rank: Regular Contributor
timestamp: November 25, 2020, 01:07:34 am
content: Quote from: Ian.M on November 21, 2020, 02:03:27 pmI am curious so I did the experiment... and all four containers turned to slime.I could tell within an hour that they were getting viscous. After sitting a couple of days, they're all a very mucusy consistency. Maybe it's something about that bar of soap. It has been in the laundry room for a long time, but I thought using shavings off the bar should get to material deeper down in case there were any surface contaminants.I was also tempted to experiment with the resistance of the "bad" flux. After all, is one to believe a lone video on the internet? But I don't have an empty board like that, and I'm not sure it's worth potentially contaminating the new tip. Still curious, so maybe I'll try something with the old iron if it bugs me enough.Quote from: uli12us on November 21, 2020, 09:06:55 amThanks for the recommendation. The Amtech, fake and original, are often highly praised. I'm getting tired of dealing with products of questionable origins (funny to see "Made in USA" on products shipping from China), and the originals are for some reason really expensive. My use is not so specialized or critical so I will keep looking for something that is decent both in quality (i.e. has a data sheet) and price.Quote from: tooki on November 21, 2020, 05:07:49 pmThanks for the detailed research. I hadn't heard of newark, but yes, digikey and mouser are the classic paradises. The main challenge with them is shipping costs which make small orders not really cost effective. But their selection is fantastic. Maybe I'll build up a shopping list to make a bigger order worthwhile eventually.That SRA FLS135 is also on amazon.ca and I had seen it a while back but passed because it seems strange... hard as beeswax and some of the review pictures make it look not so appealing. The Caig RSF-R39-2 looks interesting, but $20 for flux? I guess if I have no choice..Regarding solder, what about Kester 44 ? I can find some locally for $20/lbs for Sn60 alloy, 0.040 mil (1 mm) diameter, core size 50. The only drawback I see is that the data sheet says residues will not be cleaned with IPA, but it also says it doesn't need to be cleaned in most cases. Kester 285, classified ROL0 vs the 44's ROM1, seems like the ideal choice, and the data sheet again says cleaning is not needed in most cases but there's no mention of the effect of IPA on residues. But is the 285 worth 2-3X the cost of the 44?Quote from: Electro Fan on November 21, 2020, 09:43:54 pmThanks, I hadn't heard of All-Spec. I called them and they do ship to Canada and in fact their parent company has a warehouse in Toronto:https://www.all-spec.com/hiscocanThe downside is they have a minimum order size of $50.

author: Electro Fan
author_rank: Super Contributor
timestamp: November 25, 2020, 04:00:48 am
content: Quote from: cigmas on November 25, 2020, 01:07:34 amA few thoughts:I think you will find that Kester makes very good products - so it could just be a matter of which version of their many solder products is right for you. I think it will come down to which of their lead or lead-free solder products you prefer.FWIW, here are a couple likely contenders:I settled on this:Kester 24-9574-1402 Lead Free 48 RA Solder Wire, .031" dia., Core Size-66 Sn99.3Cu0.7https://www.all-spec.com/Product/24-9574-1402-16600- Lead free requires a higher temperature which I don't think is as desirable for parts and boards, but I went with LF.- This product is their 48 RA (Rosin Activated) version with a rosin core size of 66 which = 3.3% flux core (you might not need much more flux when you use this but I keep some flux in a pen around just in case something is stubborn).http://media.hiscoinc.com/Volume2/d110001/medias/docus/223/Kester%20Inc-32285_48-RA-TDS_VD.pdf- This version has no silver in so it so it is considered part of their K100LD product line.https://www.kester.com/DesktopModules/Bring2mind/DMX/Download.aspx?Command=Core_Download&EntryId=1249&language=en-US&PortalId=0&TabId=96Pretty sure this is the best even though I decided to go with Lead Free:Kester 24-6337-0027 44 RA Solder Wire, .031" dia., Core Size-66 Sn63Pb37https://www.all-spec.com/Product/24-6337-0027-16600- This is probably the best performer - easiest/nicest/best looking (beautiful) solder joints at the lowest temperature.As for the $50 minimum at All-Spec you might want to check to see if that is truly the minimum or if it's just the minimum that qualifies for free shipping. Even if a Kester 1 pound reel is $25-$30 and you have to pay ~$7 or whatever for shipping it's still worth giving Kester and All-Spec a try. Or you could order your two finalist types of solders and try both and maybe qualify for free shipping. Part of electrical engineering is experimenting via comparison, I think.

author: cigmas
author_rank: Regular Contributor
timestamp: November 26, 2020, 06:06:14 am
content: Thanks for bringing up the lead-free solder. I've never used it but it might be worth considering for the long term. I always worry about the disposal of the used solder.Interesting to see this recurring detail about Kester's rosin core in the Cleaning section:QuoteFrankly the bundle of solder I have has so far lasted over a decade, and at my current rate of use it will take at least several more years before it runs out. The array of options in solders and fluxes is dizzying, so I'll keep reading (data sheets) until a choice becomes clearer.Quote from: Electro Fan on November 25, 2020, 04:00:48 amJust off by an order of magnitude. I created a dummy account to get shipping quotes (hate it when they force that) and the cheapest shipping option with USPS for 3 lbs of solder worth ~$70 USD is over $60 USD just for the shipping. Fedex economy shipping costs over $100 USD.The order page unambiguously states "We require a minimum order of $50". The top banner advertises free shipping on orders over $199 valid only in the continental US.

author: Electro Fan
author_rank: Super Contributor
timestamp: November 26, 2020, 06:15:26 am
content: Quote from: cigmas on November 26, 2020, 06:06:14 amSounds like it’s time to be happy with your current solder

author: cigmas
author_rank: Regular Contributor
timestamp: November 26, 2020, 06:32:10 am
content: Quote from: Electro Fan on November 26, 2020, 06:15:26 amI can certainly be thankful for it.

author: tooki
author_rank: Super Contributor
timestamp: November 26, 2020, 06:46:56 am
content: Quote from: cigmas on November 25, 2020, 01:07:34 amThe SRA flux looks just like how I remember Kester 44 flux paste as being. (They don’t make it any mode.)As for cost, I guess you haven’t browsed for flux lately. Many modern fluxes are crazy expensive. Some cost US$60 for a 10cc syringe...As for the solder, part of that price difference is the flux, part is the alloy, part is the diameter. The thinner the solder, the more expensive, generally speaking. IMHO 1mm is too thick for most modern soldering - 0.7-0.8mm is my most used, followed by 0.5mm, and very rarely 0.3-0.4.Kester 44 is a great flux, in fact it’s what I have at home now. But Kester’s datasheets say the 285 has appreciably better activity, despite being a milder flux, chemically speaking. 44 can be removed with IPA, no-clean generally cannot, leaving white residues. So proper flux cleaner is mandatory if you want to remove no-clean, but frankly it’s advisable for rosin fluxes like 44 as well. You need far less flux remover than you would IPA alone, and it does the job much quicker.As for the alloy, I prefer 63/37, but it’s practically indistinguishable from 60/40. Lead free is fine, but leaded is a smidgen easier to work with. (Lead free is not the end of the world many claim it to be.)

author: uli12us
author_rank: Contributor
timestamp: November 26, 2020, 05:00:49 pm
content: If you want to try LF solder, we in germany must use these, because we can't get any leaded solder since 3 or so years.But fortunately I have 1 lb bought before prohibition, I hope it will be as priceless as alcohol during prohibition in USA.But because 1mm its to thick, I had like a 0,5 or so and can't buy it from a good source for a non prohibitive price because of shipping costs.I have tried the felder NI+. it is originally a fuji patent from Japan. the solder points look the same as from SnPb solder.https://www.reichelt.de/de/en/lead-free-solder-with-copper-1-0-mm-250-g-lz-f4-bf-1-0-250-p258994.html?GROUPID=557&START=0&OFFSET=16&SID=953668417487ae684286847da7848ef479ddc7295e2c1e2465df1&LANGUAGE=EN&&r=1The solder flows, like a leaded one and the surface appears the same. the only disadvantage is the higher temperature.I think you can buy it in canada, similar we can buy Kester in Europe.Or you can use Ebay, Amazon to buy it worldwide with low shipping cost.Often enough, I can't find the desired product in your country, I search for these part in other countrys,after that, I change the country in the url to de for Germany, or you ca for canada.So I can buy the part in my country, although the offer isn't officially for my country.

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: November 26, 2020, 05:13:46 pm
content: You can make solder tips out of small brass rods or bolts, just use a file or dremel to configure the tip to your needs.Usually they look terrible but work well.I sometimes use this method on some of my old soldering irons along with a Pace solder station.Dip the new tip into flux while it is warming up and then treat it with a little solder to tin it.You can regulate the temp of cheap irons with a auto transformer also

author: Ian.M
author_rank: Super Contributor
timestamp: November 26, 2020, 05:51:39 pm
content: Brass has under 30% of the thermal conductivity of copper. If you need to make custom tips for an iron that can take plain rod tips, I strongly recommend getting copper rod of the appropriate diameter.

author: uli12us
author_rank: Contributor
timestamp: November 27, 2020, 02:18:55 am
content: After that, you must galvanize the tips, to prevent from oxidising. first with iron, after that the peak of the Tip with Nickel.At least is that the normal procedure from the manufacturers of such parts.Only the simplest tips today are galvanised, they live much longer than the old copper tips.

author: helius
author_rank: Super Contributor
timestamp: November 27, 2020, 02:58:13 am
content: Maybe the usage of the word "galvanised" is different in other countries, but in English it refers to zinc plating steel for corrosion control. The word is from "galvanic protection" which describes the electrochemical cell formed between zinc and iron, where zinc is more electronegative and sacrificially oxidizes. When metal plating is done for other reasons it is just called plating.Additionally, nickel is difficult to wet with most solders unless using special active fluxes. Normal practice is to chrome plate the unused part of the tip, leaving iron exposed on the working part, and dip it into molten tin. That provides the tinned surface that solder will wet easily. The iron is protected from rust by always being tinned with solder.

author: uli12us
author_rank: Contributor
timestamp: November 28, 2020, 12:14:26 pm
content: I don*t know that until now. Galvanising in germany is generally a electrical driven coating of nearly always metal parts. Maybe plating is the better word for it.And I know that iron Plating should work for soldering tips, but in every description of the parts you can read, that they plate her parts with nickel as the last coating. Nickel will be self passivating in air, but you use always a flux, that destroys the passive film. For an amateur its easier to plate a copper part with nickel, than Iron. The last part, the chrome, is complicated, because of the highly poisonous Ingredients and the needed current 10 times higher than any other plating metal.But all of them is better, than using a uncoated copper tip.Those tips are good in roofing, soldering iron sheets together to build cases for some EMV sensitive parts or similar.But not for electronics.

author: tooki
author_rank: Super Contributor
timestamp: November 28, 2020, 08:38:53 pm
content: Quote from: Wallace Gasiewicz on November 26, 2020, 05:13:46 pmNo, you canadjustthepowerof an iron with an autotransformer/variac. But you cannotregulatethe temperature of the tip as the variac cannot respond to temperature changes at the tip.

author: cigmas
author_rank: Regular Contributor
timestamp: November 30, 2020, 12:29:42 am
content: Quote from: tooki on November 26, 2020, 06:46:56 amOh I definitely noticed those insane prices! Since soldering worked just fine before modern fluxes, and given my non-specialized use-case, I'm inclined to opt for less expensive tried-and-true options.Good to know about your preferences for the solder diameter. I was wondering how usable 1mm might be, since my current solder is ~0.8mm and I don't find myself wishing it any larger.Quote from: tooki on November 26, 2020, 06:46:56 amI'm really confused, because I find no reference to a flux called Kester 44, only solder wire. And Kester 44's data sheet explicitly states "IPA will not clean the residues off the surface of the circuit board after the soldering process. A saponifier or cleaning agent specifically designed to clean a rosin based flux is required to clean the residues. Please contact Kester Technical Support for further information."Quote from: tooki on November 26, 2020, 06:46:56 amQuote from: uli12us on November 26, 2020, 05:00:49 pmReassuring comments about lead-free solder. I'm tempted to try it. I can't find Felder NI+ available to Canada, but Kester's lead-free options are easier to find for me.

author: helius
author_rank: Super Contributor
timestamp: November 30, 2020, 01:32:07 am
content: Quote from: cigmas on November 30, 2020, 12:29:42 amIt used to be available in a paste form (called "SP44"). The closest thing to 44 in liquid form is Kester 1544. While cleaning is not absolutely necessary (it is supposed to be nonconductive and noncorrosive), IPA is effective at removing it. The warning from Kester is probably about halides remaining after IPA brushing (the "white bloom effect"). This is a common problem when incorrect cleaning procedures are used. See thethread here.

author: Shock
author_rank: Super Contributor
timestamp: November 30, 2020, 10:45:33 am
content: Quote from: cigmas on November 30, 2020, 12:29:42 amhttps://www.kester.com/products/product/44-flux-cored-wire"Kester 44 Rosin Flux is an activated rosin formula for use in flux-cored solder wire. 44 has virtually dominated the field of activated rosin core solders for well over four decades."IPA will clean rosin but it depends under what circumstances. Remember no flux is going to magically evaporate off the board it will leave a residue that needs to be broken down and rinsed off (if required). There are too many semantics to talk absolutes, for starters at home for personal use often we would use a brush to loosen flux in a solvent that is appropriate and safe, but in a commercial environment that might not be possible or practical. So you might get Kester saying for instance "use a saponifier" which may be the preferred method, but at home that could also be the expensive method. Really at some point you just need to grab something and run with it.

author: cdev
author_rank: Super Contributor
timestamp: December 23, 2020, 12:49:36 pm
content: In my experience IPA cleaning with a toothbrush or toothbrush and cotton or foam swab will clean almost anything flux related off well enough toalmostnever cause problems, and the only situationIregularly encounter where more cleaning may be needed is with something like alow noise amplifier, which typically has biascurrent, andRFis involved. There I use citrus cleaner, averysmall amount of it and distilled water. I bet an ultrasonic cleaner would improve the clean even more. The citrus/orange makes a big difference with something like an LNA and how quiet it is even if there is no visible residue. Squeaky clean is desirable meaning no grease whatsoever.This means that there is still residue with IPA and most "no clean" flux. In a pinch just a drop - no more, of castille soap (Ive used "Dr. Bronners" peppermint soap, which also repels fleas from dogs) in distilled water not tap water, also works well for LNAs.It makes a big difference for noise figure, it seems, but I have no way to measure it.LNAs should getwashedfrom time to time if you cook in the same building.RF hardware should make this easy, seriously.

author: Teledog
author_rank: Regular Contributor
timestamp: December 23, 2020, 04:00:02 pm
content: As to the rosin flux, I've made my own for years.I'm sure I'll be flamed for this,.but..Find some decent 99% IPA, some have a residue, some don't. - put a few drops on a sheet of clean glass, let it evaporate & look for a deposit.My Costco 99% does have a residue, grocery store generic 99% - no residue.Get a block of cheap bow rosin (the stuff for violin /cello bows) - Keep the rosin in a bag/jar, as it's a bit hygroscopic.Break some off & crush it a bit & add some IPA - mix until dissolved - thin it out if you use it in a pen - or make your own custom thick stuff - keep it in an eydropper or small bottle.Clean up with IPA after soldering.Always worked well for me!I DO use that thick commercial rosin base "goop in a tube" for BGA reballing/replacement though - with plenty of cleaning after.Never liked "no clean" or water soluble..always sh*tty joints.G'Luck!

author: tooki
author_rank: Super Contributor
timestamp: December 23, 2020, 04:59:52 pm
content: Quote from: cdev on December 23, 2020, 12:49:36 pmI assure you, many modern fluxes aren’t even remotely effectively cleaned with IPA alone. At work, the Stannol solders we use (mostly KS115), after cleaning with IPA, look like you’d taken the joints and put glue on them and then dusted it with baking soda. Whatever non-rosin components are in that flux simply don’t dissolve in IPA at all, leaving the joints absolutely covered in crud. No amount of rinsing makes any difference, since the problem isn’t redeposition, but not dissolving to begin with. A much smaller amount of real flux cleaner (like the Electrolube flux cleaner we use) removes it thoroughly and with far less effort.With Kester 44, I find that while IPA ultimately cleans it effectively, real flux cleaner does it much faster and with less effort. Here in Switzerland, pure IPA is relatively expensive, so using real flux cleaner is only trivially costlier, and the time savings and superior result are well worth the bit of added cost.

author: tooki
author_rank: Super Contributor
timestamp: December 23, 2020, 05:33:17 pm
content: Quote from: Teledog on December 23, 2020, 04:00:02 pmI’ve made rosin-in-IPA before, and while it does work, it’s simply not as good as real flux, especially for tarnished components.As for rosin being hygroscopic: not really... Rosin is used as a waterproofing agent. It does tend to clump up, but that’s not because it’s absorbing moisture.Quote from: Teledog on December 23, 2020, 04:00:02 pmModern no-clean fluxes exceed the performance of older, non-no-clean fluxes. I’ve been wanting to try Kester 285, which they specify as having far superior wetting and flow than the excellent 44, which is a traditional rosin flux. And modern no-clean paste fluxes are great.I don’t have any personal experience with water soluble, but given how widely used it is, it’s not likely to perform poorly.

author: Renate
author_rank: Super Contributor
timestamp: December 23, 2020, 09:13:58 pm
content: Quote from: tooki on December 23, 2020, 05:33:17 pmWell, I don't know what they were using, but years ago I ran into some hand soldered circular connectors on some British equipmentand the resistance between two pins was about 10 k.

author: Psi
author_rank: Super Contributor
timestamp: December 24, 2020, 12:22:20 pm
content: Quote from: tooki on December 23, 2020, 05:33:17 pmI've been using 285 for a while.no complaints

author: tooki
author_rank: Super Contributor
timestamp: December 24, 2020, 12:57:20 pm
content: Quote from: Renate on December 23, 2020, 09:13:58 pmWell sure, a rosin-basedfluxresidue definitely can be conductive and/or hygroscopic, depending on what else is in it. Rosinitselfisn't meaningfully hygroscopic. Many (most?) rosin fluxes are designed to be non-conductive to the point that for most applications, they don't need to ever be removed, and one can find rosin flux residues on (working) electronics from well over 50 years ago, still rock hard. (Rosin-based no-clean fluxes simply increase compatibility with sensitive circuits.)

author: tooki
author_rank: Super Contributor
timestamp: December 24, 2020, 12:57:53 pm
content: Quote from: Psi on December 24, 2020, 12:22:20 pmThanks for the feedback! How is it to clean off the board?

author: Psi
author_rank: Super Contributor
timestamp: December 24, 2020, 05:46:49 pm
content: Quote from: tooki on December 24, 2020, 12:57:53 pmI do a scrub with a brush in iso, then a fresh iso rince, then use compressed air to blow away the iso before it can evaporate and leave behind streaks.Never had any probs.

author: GreyWoolfe
author_rank: Unknown
timestamp: December 24, 2020, 10:19:14 pm
content: Just to throw my 2 pence into the pot, I use MG Chemicals 835, both in a squeeze bottle with a hypodermic needle and a bottle with a brush. I use Kester 44, 63/37 solder .031"/.80 mm and AIM LF SN100C .020" Glowcore 2.5%. I have a dedicated tip for LF so there is no cross contamination. I have a Hakko FX-951 and a Metcal MX500. Ialwaysclean the pcb when done, I want it to look like I never touched the board. I use 99.995% IPA onto a Kimwipe and I scrub the Kimwipe on the work area with a toothbrush. When the flux is gone, I clean the area again with a Kimwipe and more IPA. Spending a little extra for good consumables and lots of practice will make life so much easier.I learned my soldering at ITT Technical Institute with the cheap crap firesticks that the school provided. We were also graded on our soldering so we learned quick or lost points. I have thought once or twice about making a soldering video. There is way too much noise on the web. I would rather teach in person so there is real time feedback like when I did a soldering class for my Ham Radio club. I also don't want to subject people to my New Jersey accent. At least at the club, they are used to me.

author: Electro Fan
author_rank: Super Contributor
timestamp: December 25, 2020, 05:44:04 am
content: Quote from: Teledog on December 23, 2020, 04:00:02 pmThanks for the glass test.I tried the test with 3 Isopropyl Alcohols ranging from 70% to 99.9%. The 70% left the most white residue, the 99.9% left the least.