Tips for desoldering a potentiometer? - Page 1
Forum section: electronics / beginners

author: YurkshireLad
author_rank: Frequent Contributor
timestamp: February 02, 2023, 06:34:04 pm
content: I created a simple PCB board at home, but I subsequently found a problem with it. I want to remove the components and rebuild on another board (or the same one if it survives), but I'm having trouble desoldering the potentiometer. I've tried a solder sucker (the cheap ones from Amazon) and some solder wick. I am using a microscope to check the pins as I go, but no matter what I try, I can't free all three pins. So any suggestions would be greatly appreciated! Thanks

author: BILLPOD
author_rank: Frequent Contributor
timestamp: February 02, 2023, 06:39:51 pm
content: I've got one of these, for just such jobs.https://www.amazon.com/Station-Soldering-Airflow-Adjustable-Desoldering/dp/B07T9KLHY5

author: YurkshireLad
author_rank: Frequent Contributor
timestamp: February 02, 2023, 06:49:00 pm
content: Quote from: BILLPOD on February 02, 2023, 06:39:51 pmThanks. I read several posts on here about various cheap stations, and generally people said to avoid them. Especially some that require power supply mods etc.. I could consider one if there's one at the right price that doesn't require mods to improve safety.

author: themadhippy
author_rank: Super Contributor
timestamp: February 02, 2023, 07:37:18 pm
content: get as much solder out with your wick or sucker,then wiggle/pull the pot as you heat one pin at a time.

author: YurkshireLad
author_rank: Frequent Contributor
timestamp: February 02, 2023, 07:45:20 pm
content: Quote from: themadhippy on February 02, 2023, 07:37:18 pmI tried that, but maybe I'll try again.

author: CountChocula
author_rank: Unknown
timestamp: February 02, 2023, 07:57:07 pm
content: Depends on the topology of the pins… if they're inline, you can solder a length of bare solid-core wire across all three terminals, then place your iron on one pin so that it wedges the wire in place. The wire propagates the heat to all three pins, which melts the solder on all of them at the same time and allows you to pull the pot out without bending or damaging the leads. You can then either suck or wick the remaining solder out of the mounting holes. It helps if you have a third hand to hold the board and a pair of tweezers so that you don't burn your fingers when you pull out the component

author: Infraviolet
author_rank: Super Contributor
timestamp: February 02, 2023, 08:54:10 pm
content: Ideally you have two people, one to put pliers on the stubborn component and give it a gentle but constant tug, the other with desoldering braid and the iron as hot as it will go heating the pins from the other side. In the absence of two people a good fit in some sort of vice can help hold the board. Sometimes putting a bit more solder back on to the pins can help, then sucking it off with the braid again. Sometimes this makes the solder being sucked of come away together rather than leaving bits stuck in irritating places. Use leaded 60/40 or 63/37 solder if you have it. Also, there are products made which are very low temperature solder like alloys (something called chipquik I think) which can be applied like solder and then take all the actual solder away with them when you desolder, that could be something to look in to in future. But I think mainly just trying again and again with braid is the best option, and get the iron very hot, much hotter than the temperature you usually use when soldering. The other thing that might help if you have it is a flux pen, if you drip some flux on the area that may make the stubborn solder flow away more easily.

author: YurkshireLad
author_rank: Frequent Contributor
timestamp: February 02, 2023, 09:23:18 pm
content: Thanks. This is a through hole pot. I just got a flux pen so I'll also try that.

author: pcprogrammer
author_rank: Super Contributor
timestamp: February 03, 2023, 06:32:10 am
content: Quote from: CountChocula on February 02, 2023, 07:57:07 pmI second this. When the pins are close enough or even a bit further away or in a triangle shape just take some 1.5mm2 or even 2.5mm2 solid copper wire and extend your soldering tip with it. (Twist the copper wire around the tip) and apply more solder. With all the pins sitting it liquid solder it is easy to remove the part. Then you can clean up the board with a solder sucker or wick.

author: Kujo
author_rank: Newbie
timestamp: February 03, 2023, 09:34:06 am
content: I also agree with this method. Having worked on numerous old guitar amplifiers sometimes the only way to get them out is to have all the pins bathed in liquid solder and then a good wiggle.The things you find in old guitar amps.Kujo

author: Haenk
author_rank: Super Contributor
timestamp: February 03, 2023, 10:14:58 am
content: For multilayer boards, I often use hollow needles; there are sets readily available on ebay and Amazon and of course Aliexpress, about 5-10 EUR/USD per set.

author: pcprogrammer
author_rank: Super Contributor
timestamp: February 03, 2023, 11:01:19 am
content: Quote from: Haenk on February 03, 2023, 10:14:58 amTo shove over the pins you mean?I sometimes use a very small screwdriver to open up the hole when suction or wick does not work in probably the same manor. Heat up the pad and gently pry the screwdriver tip in the hole. Solder does not stick and after cool down the screwdriver can be easily removed and the hole is open.Can you provide a link to the types you use?

author: Haenk
author_rank: Super Contributor
timestamp: February 03, 2023, 01:01:16 pm
content: I use this type of set:https://www.ebay.de/itm/194714520443Works surprisingly well, however I usually only need the smallest diameter, and that needle will bend easily.

author: pcprogrammer
author_rank: Super Contributor
timestamp: February 03, 2023, 01:34:59 pm
content: Thanks, this gave me the term to search ali withhttps://nl.aliexpress.com/item/32847612552.htmlhttps://nl.aliexpress.com/item/32574393988.htmlLook like the same sets.

author: shapirus
author_rank: Super Contributor
timestamp: February 03, 2023, 02:50:14 pm
content: Quote from: pcprogrammer on February 03, 2023, 01:34:59 pmNow that's a handsome margin: 7.49 GBP in the UK vs 1.93 USD, shipping included, from Ali. Maybe there's an even cheaper offer, but I didn't bother to search further. Thanks, now I will own one more thing sitting on the shelf to collect dust with.

author: Shay
author_rank: Regular Contributor
timestamp: February 03, 2023, 04:42:47 pm
content: A good old wick should work just fine.First, add some fresh solder onto the pads.Take your wick and place it on top/side of the pad, and heat it with soldering iron. Keep wiggling the soldering iron with the wick, after a while it should suck it all out. If there is a lot of solder, you might need to this a few times. I am quite positive the issue is just a lack of technique, and not the lack of tools.

author: YurkshireLad
author_rank: Frequent Contributor
timestamp: February 03, 2023, 04:43:36 pm
content: Quote from: Shay on February 03, 2023, 04:42:47 pmOh I have no doubt it's a lack of technique!

author: shapirus
author_rank: Super Contributor
timestamp: February 03, 2023, 05:08:48 pm
content: Quote from: Shay on February 03, 2023, 04:42:47 pm...and spare no flux in the process!

author: Haenk
author_rank: Super Contributor
timestamp: February 03, 2023, 06:11:13 pm
content: Quote from: Shay on February 03, 2023, 04:42:47 pmLately I had some multilayer boards with some very nice components (so they had to come off) - due to extreme shielding and grounding planes, the PACE desoldering station did not help a lot, wick and flux did not help either, low melt solder helped a bit - eventually, I could free the remaining pins with the smallest needle. So: Give it a try!

author: tooki
author_rank: Super Contributor
timestamp: February 03, 2023, 06:16:25 pm
content: Or just preheat the board with hot air.

author: donlisms
author_rank: Frequent Contributor
timestamp: February 04, 2023, 08:52:09 am
content: For some parts, after wicking away as much solder as possible, you can sorta press on the side of the lead with the iron to melt/pop it away from the sides of the hole. It will give a little "snap", and break free of the tiny bit of solder that remains. The lead will then wiggle if you test it with the tip.That's one. Do the rest, and pull the part off.

author: pcprogrammer
author_rank: Super Contributor
timestamp: February 04, 2023, 09:03:33 am
content: Quote from: donlisms on February 04, 2023, 08:52:09 amBut do not do this with JBC or similar solder iron tips, because they can't handle mechanical stress that well.

author: RoGeorge
author_rank: Super Contributor
timestamp: February 04, 2023, 09:18:29 am
content: Use the most powerful soldering iron you have, even if it's not a temperature-controlled one.Coil a thick copper wire on the soldering iron, with a loop, or two wires with the loose end shaped like a dipole.Keep it very short, so it won't lose much heat. Bend it such that it will heat all 3 terminals at once.Put plenty of solder on the bent wires. Put plenty of flux paste on the PCB, at the 3 solder joints.Place the PCB in a vice, or ask somebody else to keep the PCB still for you.Now melt all 3 solder joints at once and extract the 3-terminal potentiometer.Later edit:-------------I've searched for an online pic but couldn't find any. The closest is this one where a whole IC is desoldered, except the helping copper wire is not coiled around the soldering iron:https://electronics.stackexchange.com/questions/51616/is-this-desoldering-hack-likely-to-work

author: uli12us
author_rank: Contributor
timestamp: February 04, 2023, 11:11:27 am
content: If the potentiometer is only soldered with the 3 pins, than the easiest way is to cut of the pins, desoldering the pins in the board pin for pin and solder a wire between the Potentiometer and the board.