Cleaning my PCB - Page 1
Forum section: electronics / projects

author: MattHollands
author_rank: Frequent Contributor
timestamp: December 13, 2015, 06:30:14 pm
content: Hi! I'm working on a tiny IR TV remote. I just finished populating the board, but I'm fairly certain that there is some stray solder paste in there (e.g. under switches). Right now there are no shorts or anything, but I'd like to try and clean the board to be sure. The board can be seen here.https://keepdevelopingprojects.wordpress.com/2015/12/13/project-remoteli-fully-populating-board-v2/I have a hot air gun lying around the house but I don't think it's made for soldering, so most of this board was done with a soldering iron. I think using water probably isn't a good idea because it could get caught up under the switches.Is there a good way to do this?

author: davebb
author_rank: Frequent Contributor
timestamp: December 13, 2015, 07:32:35 pm
content: Hi use IPA to clean pcb, if there is solder balls under components that you can not get to with a brush or air you may need to use a ultrasonic cleaner,but get your self some IPA.Dave 2E0DMB

author: MattHollands
author_rank: Frequent Contributor
timestamp: December 13, 2015, 08:04:16 pm
content: Hi Dave, I only know IPA in the context of beer. In which case I will get some IPA. But I suspect you mean a different acronym?I'm looking at aerosol flux removers now

author: KL27x
author_rank: Super Contributor
timestamp: December 13, 2015, 08:19:00 pm
content: Maybe try using regular flux if you are using a soldering iron. Put the solder on the iron tip and touch it to the fluxed joint. Kinda like using solder paste but in two parts.

author: halloween360
author_rank: Contributor
timestamp: December 13, 2015, 09:13:42 pm
content: What type of solder paste did you use when assembling your board? I have become really fond of the solder paste that Kester makes that is water soluble. I use it in all my boards. Here is the leaded paste digi # KE1512-ND. I just run warm water over the boards and scrub them really good with a tooth brush. The flux will foam as you scrub. When the board quits foaming the board is clean. I then allow my boards to either dry overnight or place in a dry cabinet for a few hours and they are good to go.

author: CrashO
author_rank: Unknown
timestamp: December 13, 2015, 09:30:15 pm
content: Quote from: MattHollands on December 13, 2015, 08:04:16 pmIsoPropyl Alcohol / isopropanol, has a bit less Hop in comparison with the beer

author: MattHollands
author_rank: Frequent Contributor
timestamp: December 13, 2015, 09:56:15 pm
content: I'm using SN63/PB37 from MG chemicals

author: Pjotr
author_rank: Frequent Contributor
timestamp: December 13, 2015, 10:19:31 pm
content: IPA (isopropanol, not the beer) only dissolves the flux and only when it is not been overheated or heated too long. The effect is that the dissolved flux spreads out over the board unless you wipe it off thoroughly with a tissue or something. That will not work underneath components.B.t.w. beer for cleaning (and I guess, the brand doesn't matter), it is quite conductive. Have tested that a few years ago with a keyboard

author: zapta
author_rank: Super Contributor
timestamp: December 14, 2015, 12:05:46 am
content: I am using similar switches (Digikey CKN10502CT-ND) and they don't do well under wet cleaning. I am using IPA, brush and Kimwipes for lifting but these switches are not sealed and some of them stopped making a connection. I now clean the boards much more carefully around the switches.https://www.eevblog.com/forum/projects/why-these-tactile-switches-failing-on-me/

author: MattHollands
author_rank: Frequent Contributor
timestamp: December 14, 2015, 02:51:55 am
content: Ok, thanks guys, I'll have to get some IPA too!