EEVblog #997 - How To Solder Surface Mount Components - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: June 02, 2017, 01:54:30 am
content: Soldering the Nixie Tube display PCB. How to do drag and dab soldering to make surface mount parts soldering easy.Also a look at the Elecrow blank prototype PCB quality.Jump to 3:36 for the soldering tutorialPart 6 of the Nixie Tube project

author: tautech
author_rank: Super Contributor
timestamp: June 02, 2017, 02:18:01 am
content: You didn't make mention of populating with passives first to help minimise ESD risk to active devices.Obviously there weren't many on this layout but wouldn't you do that first ?

author: piranha32
author_rank: Unknown
timestamp: June 02, 2017, 02:23:43 am
content: Drag soldering works really great, but you need to have enough solder on the tip. That's why big tips work so well. Many manufacturers also offer "mini-wave" tips with decent-sized reservoir for molten solder.Here's how Pace's mini-wave tip works. Note how big the tip is compared to the chipHowever, my favorite home-shop method of soldering SMD components is hot-air reflow. I just tin the pads, flux the board, place components, and reflow. No need to mess with stencils, works great each time, is very quick, and with a little bit of practice gives really professionally looking board.

author: mdszy
author_rank: Unknown
timestamp: June 02, 2017, 02:28:16 am
content: Nice, loved the video!I'm going to be working on a modular nixie clock project. A four-digit nixie display that will allow for swapping out a "driver" board so you can use it to display any information you'd like, or use alternatively clock drivers. For instance, I'm going to try making one with discrete logic, then an ATTiny based clock, maybe a GPS-time based one, etc. etc.Those pins look awesome, I was under the impression that it's either sockets or nothing, but now I really want to pick up a lot of those nixie pins! Thanks for the great vid!

author: abdullahseba
author_rank: Frequent Contributor
timestamp: June 02, 2017, 03:41:48 am
content: Just been watching this and wondered ho you keep your tip shiny? Mine always goes black and is useless there is a tiny bi of solder on the to transfer the heat.

author: tautech
author_rank: Super Contributor
timestamp: June 02, 2017, 03:53:23 am
content: Quote from: abdullahseba on June 02, 2017, 03:41:48 amBrass or stainless wool takes the grud off the tip and at the same time wipes solder all over it. Hakko do a brass sponge but you can also use a soft domestic stainless scourer.There are wool holders but a smallish ceramic cup works just as well.Stab, stab and hey presto clean tip.

author: HackedFridgeMagnet
author_rank: Super Contributor
timestamp: June 02, 2017, 04:33:14 am
content: Quote from: abdullahseba on June 02, 2017, 03:41:48 amYes clean tip before/during soldering.But for me the important bit is, when you are finished don't clean it, instead put a big blob of solder on the tip and then turn it off.

author: abdullahseba
author_rank: Frequent Contributor
timestamp: June 02, 2017, 05:15:19 am
content: I have a brass one on the hakko FX-888D. Do you have to do it vigorously?

author: tautech
author_rank: Super Contributor
timestamp: June 02, 2017, 05:40:49 am
content: Quote from: abdullahseba on June 02, 2017, 05:15:19 amNo.Just a stab or two of a hot iron into the wool is enough. Try it a few times and you will find what works best for you.

author: P90
author_rank: Frequent Contributor
timestamp: June 02, 2017, 06:06:30 am
content: Quote from: tautech on June 02, 2017, 03:53:23 amthey make a "soft" stainless steel scrubber?

author: plazma
author_rank: Frequent Contributor
timestamp: June 02, 2017, 06:21:32 am
content: Don't use stainless wool. It ruins the tip.

author: Fungus
author_rank: Super Contributor
timestamp: June 02, 2017, 07:19:45 am
content: Quote from: abdullahseba on June 02, 2017, 03:41:48 amYou're supposed to clean it before use and every 20 minutes or so as you work. Use the sponge, make it damp with water so it doesn't burn (ie. not a puddle of water).Once it's all blackened it's quite hard to fix. Better to get a new tip and look after it this time.

author: P90
author_rank: Frequent Contributor
timestamp: June 02, 2017, 07:25:33 am
content: Quote from: Fungus on June 02, 2017, 07:19:45 amThat's what she said...

author: abdullahseba
author_rank: Frequent Contributor
timestamp: June 02, 2017, 07:32:51 am
content: Quote from: P90 on June 02, 2017, 07:25:33 amErr? She who? where? what?

author: P90
author_rank: Frequent Contributor
timestamp: June 02, 2017, 07:37:26 am
content: Quote from: abdullahseba on June 02, 2017, 07:32:51 ammarhabaNot a fan of "The Office" ? LOL

author: abdullahseba
author_rank: Frequent Contributor
timestamp: June 02, 2017, 07:39:31 am
content: Quote from: P90 on June 02, 2017, 07:37:26 amOhhh

author: EPTech
author_rank: Regular Contributor
timestamp: June 02, 2017, 07:48:59 am
content: Hi there,The dab technique is also great for removing a short from between legs.It is an alternative method to using solder wick that is less stressful to the legs and pads.1. Apply some gel flux between the legs.2. Put some solder on the tip and clean it off so you end up with a shiny but dry tip.3. heat up both pads at the same time at a small angle with a very small amount of pressure on the end of the pins, just touching them actually4. the excess amount of solder should be pulled towards the solder iron. Often it will help to move the tip back and forth to pull the solder away and to prevent overheating, especially when using a fixed temperature tip like I do.5. If I cannot get the short out, I use solder wick. But when using solder wick it helps to wet the tip a little bit to get the solder wick started or to cut the solder wick so that a little solder remains.Gel flux: Arcoss 23-29-10AXSolder station: OKI Metcal MFR 2000 seriesSolder wick: Chemtronics Rosin SD

author: EPTech
author_rank: Regular Contributor
timestamp: June 02, 2017, 08:15:28 am
content: Hi there,Here are some tips to keep your tip in good condition:1. When using a brand new tip. Wet it with solder as soon as it gets hot. In fact push the solder against it while it is heating.2. Dampen the sponge with demineralized water, as mineral depositions will turn your tip solderphobic and they are hard to clean off.3. The sponge must not be wet. If you hear a hiss, the sponge is to wet. The temperature shock will crack up the protective coating of your tip.4. DO NOT use abrasives to clean the tip. Always use the least abrasive method first. Use the sponge to clean the tip in between one or several solder joints. Use the brass only if the damp sponge does not work.5. Always wet the tip with solder before putting the iron in the stand for a longer time, like in between measurements or coffee breaks or after you finished.In case of a black tip you can use a "tip reviver" as a last resort but it is a very aggressive flux. Alternatively you can use a box knife and scrape of the black stuff. Hold the blade perpendicular to the tip in doing so. Use very little down force and move back and forth until the shiny surface reappears. Do not try to do the entire tip at once. When you get a shiny bit, apply solder to it and clean of. This method beats the sand paper method because you have more control and visual feedback of what you are doing. The sand paper grains will make deep grooves in the tip in an uncontrolled manner. I know it sounds weird but the knife beats the sand paper if there is no other way. I would say steel wool is somewhere in between.Hope this helps. Happy soldering.

author: tautech
author_rank: Super Contributor
timestamp: June 02, 2017, 08:44:46 am
content: Quote from: P90 on June 02, 2017, 06:06:30 amYep but if you prefer brass it doesn't last as long as SS.Quote from: plazma on June 02, 2017, 06:21:32 amHasn't done for any of the few I use.Quote from: Fungus on June 02, 2017, 07:19:45 amNah, use some form of metal wool.Why would Hakko make brass wool holders and supply brass sponge replacements ?Maybe they know something you don't.Our time at the bench is too valuable to waste pissing around with wetting sponges and fiddling to get tips clean and properly tinned.Sure if you are soldering all day and everyday , hopefully you'd have learnt how to maintain a tip. For those of us that don't have a iron in our hands all day and just want to get on with soldering every now and then metal wools are a very viable option.Never a blackened tip while using wool and the tip remains completely and perfectly tinned.

author: NivagSwerdna
author_rank: Super Contributor
timestamp: June 02, 2017, 09:35:49 am
content: Really nice video. The Elecrow boards look great. As I got older I didn't realise how my eyesight had degraded but with sufficient magnification SMD is a joy.Perhaps there should be an EEVBlog approved Stereo Widefield scope?I like the use of thehttps://threeneurons.wordpress.com/nixie-power-supply/hv-supply-kit/PSU, that's the design I went for my own implementation and works well. The design of that is almost worthy of a video itself.Looking forward to seeing the end result. (Don't forget to add some slot-machine style cycling of digits... otherwise the Nixie police will be out to get you).

author: timgiles
author_rank: Regular Contributor
timestamp: June 02, 2017, 09:55:49 am
content: Great video - been waiting for an update on the Nixie tube project. Hoped it would not turn out to be something started but never finished.My feeling on SMD techniques are to find the one that works for you. I believe it is dependent on the soldering equipment you have, what type and quality of solder etc.. you can get and how they work together. It's important to encourage new EEs to try the different techniques and understand if they produce a working PCB that lasts, that is the most important outcome.Is the PI board ordered and progressing?Oh almost forgot : covfefe!

author: Halcyon
author_rank: Unknown
timestamp: June 02, 2017, 10:34:01 am
content: Dave, are you doing anything different with the encoding/format on this video? It's the only one I can't view using my regular browser (Opera version 36.0.2130.80). Every other video on your channel loads fine.I get the error"Your browser does not currently recognise any of the video formats available".It's the first time I've ever seen this error on any Youtube video.

author: Monkeh
author_rank: Super Contributor
timestamp: June 02, 2017, 02:00:48 pm
content: Quote from: tautech on June 02, 2017, 02:18:01 amI tend to do ICs first as the passives often limit the room to work.Static's easily enough controlled.

author: tchicago
author_rank: Regular Contributor
timestamp: June 02, 2017, 07:38:03 pm
content: A fingerprint is imprinted into the solder mask at 3:13, top left.

author: NivagSwerdna
author_rank: Super Contributor
timestamp: June 02, 2017, 09:25:27 pm
content: Quote from: tchicago on June 02, 2017, 07:38:03 pmI think it's in the centre of the board, positioned where a grubby ozzie pulled it out from the stack of 7.

author: julian1
author_rank: Frequent Contributor
timestamp: June 02, 2017, 10:48:13 pm
content: Good video. Gets the point across that smt is easy, with even the most basic equipment, once you know the technique/s.

author: alank2
author_rank: Super Contributor
timestamp: June 02, 2017, 10:52:17 pm
content: I always see the flat/blunt/hoof method of soldering SMD, but I do almost all of it one pin at a time if it is 0.8mm or bigger. Smaller than that it does get a little tougher, but it can still be done. I use water soluble flux which helps tremendously.

author: Halcyon
author_rank: Unknown
timestamp: June 03, 2017, 01:42:47 am
content: Quote from: Halcyon on June 02, 2017, 10:34:01 amDisregard -- It's working now. Maybe Youtube was taking longer than usual to encode.

author: Unknown
author_rank: Unknown
timestamp: June 03, 2017, 03:03:38 am
content: Quote from: alank2 on June 02, 2017, 10:52:17 pmSame for me. Tried drag soldering with several different irons, hoof/well tips, fluxes, solders, etc, but never could get the knack of it. One pin at a time for anything >=0.45mm pitch (under a microscope - my eyes are getting old). I'm only a hobbyist & find soldering relaxing, so also rarely use reflow/paste except for *FN parts.

author: German_EE
author_rank: Super Contributor
timestamp: June 03, 2017, 07:21:20 am
content: I solder the standard passives first, then the semiconductors. Finally I solder the devices that are heat sensitive such as polystyrene capacitors and inductors in plastic formers.Don't forget to wear your anti-static wrist strap whilst working.http://www.cvel.clemson.edu/Reports/CVEL-14-065.pdf

author: EEngo
author_rank: Unknown
timestamp: June 03, 2017, 05:25:44 pm
content: can someone perhaps help me with a good idea for washing the boardsFor me, it was always very difficult to clean the boards from flux residues.What is the communities' favorite method for cleaning the boards after soldering?thanks

author: Monkeh
author_rank: Super Contributor
timestamp: June 03, 2017, 05:28:06 pm
content: I have good success with a rather aggressive suger soap (sodium carbonate + a few extras) and IPA mix in an ultrasonic cleaner. It's cheap, but it can damage stuff (any sort of switch or non-wash-sealed relay is a no-no).

author: mdszy
author_rank: Unknown
timestamp: June 03, 2017, 05:28:45 pm
content: Quote from: EEngo on June 03, 2017, 05:25:44 pmWe use isopropyl alcohol at work and a scrub brush. Works well enough for us.

author: piranha32
author_rank: Unknown
timestamp: June 03, 2017, 05:31:10 pm
content: Quote from: EEngo on June 03, 2017, 05:25:44 pmNo idea if this is "communities' favorite", but I wash first well in isopropyl alcohol (brushing with a stiff brush), then rinse with water, remove excess of water, and rinse with alcohol again to remove remaining water. Repeat the cycle if necessary.

author: jonovid
author_rank: Super Contributor
timestamp: June 04, 2017, 04:27:17 am
content: I see Dave likes orange, I have tried soldering surface mount components, yes the smaller components must go first.the big issue I had soldering surface mount is avoiding cooking the board and lifting the mask. if you are re-soldering mishaps.on a multilayer pcb project. the need for good 3D magnification.here is an idea for hobby electronics kit design.is to fabricate a proven, reliable design to pcb, then keep some, and sell off the surplus pcb's online.looks like the key is a good hobby kit design is the component symbols on the board mask and easy-to-get reliable components.maybe an idea in a hobby kit is to have some of the smaller surface mount components in part pe-assemled.letting the kit builder add some thru-hole components for the project completion. less soldering mishapsand allowing for customization. like the type of power supply or the angle orientation of a display.

author: tautech
author_rank: Super Contributor
timestamp: June 04, 2017, 04:56:12 am
content: Quote from: jonovid on June 04, 2017, 04:27:17 amA temp controlled station, quality solder and some practice fixes most of that.Magnifying headset will allow you to work down to 0603 and that's plenty small enough for the hobbyist.Daves copious use of flux was the most interesting thing that turned my head and that'll definitely reduce dwell time on the joint and hence lower the risk of lifted pads.

author: P90
author_rank: Frequent Contributor
timestamp: June 04, 2017, 05:07:11 am
content: Quote from: jonovid on June 04, 2017, 04:27:17 amSome of the kits I've purchased off ebay came with SMDs already soldered, leaving everything else to solder.

author: nctnico
author_rank: Super Contributor
timestamp: June 04, 2017, 09:18:32 am
content: Quote from: EEngo on June 03, 2017, 05:25:44 pmFlux remover. (I think) I'm using Chemtronix 'No Clean plus'.

author: EPTech
author_rank: Regular Contributor
timestamp: June 06, 2017, 09:04:11 am
content: Quote from: EEngo on June 03, 2017, 05:25:44 pmHi there,If it is just a rework or small PCB I use a spray can, like Flux-Of by Chemtronics and nothing further. To clean entire boards, like after manual assembly or highly polluted boards, I use SWAS05L from Electrolube in a recirculating wash table with a brush.When using aqueous solutions you have to rinse with tap water first to get the bulk of the wash solution of and more important, rinse with de-ionized water thoroughly to get rid of salt ions. The salts will corrode the board afterwards, with delay and for a prolonged time, so you will not notice it immediately. The last step is to blow as much of the moisture of as possible and leave the board to dry in an oven or free air.You can also clean/rinse with IPA. That required less steps. The key is: get rid of the ions after cleaning.Not all components are suited for cleaning. The first things that come to mind are relays and piezo buzzers.Most of this has already been mentioned by my colleagues on this forum. I just wanted to stress the fact that rinsing to get any ions of the board is VERY IMPORTANT!!! There I said it. Hate people who write in all capitals though.

author: jklasdf
author_rank: Regular Contributor
timestamp: July 12, 2017, 09:45:55 pm
content: Nobody's brought out the pitchforks yet for the lead-free part yet? It's surprising how common lead-free has become because of RoHS (would anyone willingly be using lead-free otherwise?). I vaguely seem to remember Dave going on rants about RoHS before, but I might just be mis-remembering stuff.