why is my desoldering braid not desoldering? - Page 1
Forum section: electronics / beginners

author: mistercris
author_rank: Contributor
timestamp: November 10, 2017, 03:47:54 am
content: Trying to use desolder braid for the first time and... nope. Not working. From the youtube vids I've seen, you put the braid on the solder, apply heat and the braid sucks it up.For me, I put the braid on the solder, apply heat and... the copper gets super hot (heat travels up to where I'm holding it), it seems to burn but almost no solder gets wicked up (copper changes color to a darker auburn - not silver from the solder like the videos I've seen) .Am I missing out on technique or did I just get really crappy braid? Boughtthis stufffrom amazon. Mainly cause it included the solder sucker.

author: Audioguru
author_rank: Super Contributor
timestamp: November 10, 2017, 03:55:03 am
content: I think you bought cheeeep Chinese junk. Why not buy high quality items locally?

author: cdev
author_rank: Super Contributor
timestamp: November 10, 2017, 04:15:36 am
content: Oxidation!Rosin flux is an antioxidant.Am I missing out on technique or did I just get really crappy braid? Bought this stuff from amazon. Mainly cause it included the solder sucker.Yes, you did get crappy braid. Try using it with added flux.

author: Dago
author_rank: Frequent Contributor
timestamp: November 10, 2017, 04:17:06 am
content: Like any kind of soldering you need to add flux. Better soldering braids have more/better flux already impregnated on them but in my experience even the cheapest chinese wick works fine when you just add flux.Other thing is that the wick is pretty effective in cooling your soldering iron, being a big piece of copper and all so desoldering some ground planes or such might be very difficult with a crappy soldering iron. Having the right size tip (the bigger the better) will make the heat transfer better.

author: Brumby
author_rank: Unknown
timestamp: November 10, 2017, 04:29:14 am
content: I saw the thread title - I had a suggestion.I saw your post - and I felt it was right.I read the other posts - and I knew I wasn't coming up with anything new or amazing.The answer is (in all probability) FLUX.

author: BMack
author_rank: Regular Contributor
timestamp: November 10, 2017, 06:12:13 am
content: Two things need to be done:1) Buy Chemtronics braid and nothing else.2) Add solder first, then desolder.

author: kalel
author_rank: Frequent Contributor
timestamp: November 10, 2017, 06:25:22 am
content: I had the same problem with the first one I bought, then I purchased the "goot wick". The "goot" one seems to be working well (well enough - I have not tried an expensive one to compare), and is not much more expensive than the first one I tried. You can find it on eBay if you can't find something at a similar price locally.As others have suggested, in any case you can add some flux to make it easier. The difference between a good and bad one is (as far as I know) that a good one has more flux already.It seems that adding flux is helpful everywhere with soldering/desoldering.

author: Ian.M
author_rank: Super Contributor
timestamp: November 10, 2017, 08:11:46 am
content: From an old topic:Quote from: Ian.M on May 11, 2016, 09:11:24 amIf there isn't a little solder at the end of the wick, it will conduct heat up it far far better than it does through it. This is aggravated by insufficient contact area between the bit and the braid:Quote from: Ian.M on November 10, 2017, 07:56:16 amAs others have already pointed out, flux is also very important. Without it the solder wont flow up the braid well, and you may even have problems getting the joint to melt quickly enough without excessive pressure and avoid pad damage. Good quality desolder braid is loaded with a lot of solid flux. Cheap braid usually isn't. Dip the end in liquid flux if you have to.Also, proper storage and handling of your braid is important:Quote from: KL27x on May 06, 2016, 07:31:03 pm^*THIS*^ - and when you are transferring braid to the small hand spool, use gloves and DO NOT TOUCH IT WITH YOUR BARE HANDS as sweat and skin oils will corrode the clean copper surface so it doesn't wick effectively. You don't have to use gloves when desoldering (and plastic or latex ones could melt so would be dangerous) as the length of braid you have touched will be used very soon, before it has time to corrode. However try to minimise the extra length you unwind to use - only unwind enough to be long enough that the lip of the hand spool doesn't melt.

author: mrpackethead
author_rank: Super Contributor
timestamp: November 10, 2017, 08:19:51 am
content: I use Goot Brand, and it works really well, have also tryed the chemtronics, and its very similar. Theres crap and good stuff. and it makes so much difference.

author: capt bullshot
author_rank: Super Contributor
timestamp: November 10, 2017, 08:21:52 am
content: Quote from: BMack on November 10, 2017, 06:12:13 amWhy? The Techspray stuff I've got here also works well.

author: ebclr
author_rank: Super Contributor
timestamp: November 10, 2017, 09:22:47 am
content: What is the power of your solder iron?

author: mrpackethead
author_rank: Super Contributor
timestamp: November 10, 2017, 10:12:22 am
content: Quote from: capt bullshot on November 10, 2017, 08:21:52 amI think you can suffice with Buy good Braid.. There is some crap stuff, but also many good brands.

author: tooki
author_rank: Super Contributor
timestamp: November 10, 2017, 11:44:56 am
content: Quote from: BMack on November 10, 2017, 06:12:13 amActually, you should try the MG Chemicals braid. It's way finer than Chemtronics, and works better in my opinion, despite being cheaper. I posted pix of both of these (and a few others) in this thread:https://www.eevblog.com/forum/beginners/desoldering-advice-please-removing-dip-ic's-without-damage/msg833426/#msg833426

author: ebclr
author_rank: Super Contributor
timestamp: November 10, 2017, 11:47:22 am
content: Just add flux and use a powerfull solder

author: mistercris
author_rank: Contributor
timestamp: November 10, 2017, 04:17:08 pm
content: Soooo, if I'm understinding, I should use flux then?Figured it'd be something like that. I hoped the positive reviews for it were legit, guess not. I'll buy better braid.As far as flux, since I need to buy some of that too, any brand recommendations? I know not to use plumbing flux.Regarding the soldering iron, I tried 2 tips (the parts I was desoldering were fairly small) a point and a small spade (I think that's what they're called) basically a standard conical tip (goes down to about 1mm) and the smallest flat tip I had (about 1.5mm 2mm maybe?).Iron started at 340 C, took it up to 360C. Solder was melting well so didn't want to take it too high.Pretty sure I cooked several components while practicing, but that's why I'm practicing on junk.

author: ebclr
author_rank: Super Contributor
timestamp: November 10, 2017, 04:33:58 pm
content: You need to use a tip with high thermal mass, fine tips will not workhttps://www.hakko.com/english/tip_selection/work_bridging.html

author: andyturk
author_rank: Frequent Contributor
timestamp: November 10, 2017, 04:35:00 pm
content: I ended up with several rolls of cheap braid, which didn't work very well on its own. But running a flux pen over the braid just before trying to use it worked perfectly (and helps use up those old flux pens that are lying around).

author: ebclr
author_rank: Super Contributor
timestamp: November 10, 2017, 04:38:11 pm
content: The secret is on the solder and tip, with the right solder and tip any brand will work some will need flux other don'tPower / thermo mass is the point here

author: tecman
author_rank: Frequent Contributor
timestamp: November 10, 2017, 05:04:05 pm
content: One thing that is important, the soldering iron tip must be wetted. Sometimes you need to add a small dab of solder to the iron to "couple" the heat to the surface (wick). If the tip is oxidized it may not effectively heat the ajoining surfacepaul

author: gnavigator1007
author_rank: Unknown
timestamp: November 10, 2017, 05:25:44 pm
content: Something that occasionally helps if the braid has been sitting too long is to pull it's width with pliers and loosen it up. I then run a flux pen over it and tighten it up again by pulling the end (just a little bit).

author: james_s
author_rank: Super Contributor
timestamp: November 10, 2017, 07:48:46 pm
content: Even the good braid goes stale after a while as the flux evaporates. I usually dip mine in liquid flux just before use, it works much better.

author: jmelson
author_rank: Super Contributor
timestamp: November 10, 2017, 07:58:05 pm
content: First, you need a LOT of heat. The braid is a good heat conductor, and sucks the heat out of the spot you are trying to desolder. So, a good soldering iron with a clean, tinned tip is pretty important.I generally have to add liquid flux to any braid I buy. The standard brands I get don't have enough.Jon

author: gnif
author_rank: Unknown
timestamp: November 10, 2017, 11:16:59 pm
content: Quote from: jmelson on November 10, 2017, 07:58:05 pmI have found when a join has a lot of mass (ie, ground plane) that cutting some of the braid off the roll to prevent the heat wicking up the length helps enormously. If you can't heat it fast enough all you end up doing is burning off the flux before it's at reflow temperature.