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DIY Stompboxes => Building your own stompbox => Topic started by: rankot on March 23, 2019, 01:51:52 AM

Title: PCB cleaning
Post by: rankot on March 23, 2019, 01:51:52 AM
Hi guys, I have bough some isopropyl alcohol so I can clean my pedal PCBs after soldering. But I have encountered an enigma - which tool shall I use to apply it? I tried with sponge and with ear sticks, but they both get shredded very soon, since most of my snapped leads are sharp.

Hints or ideas?
Title: Re: PCB cleaning
Post by: rockola on March 23, 2019, 01:59:24 AM
Quote from: rankot on March 23, 2019, 01:51:52 AM
Hi guys, I have bough some isopropyl alcohol so I can clean my pedal PCBs after soldering. But I have encountered an enigma - which tool shall I use to apply it?
Try a toothbrush.
Title: Re: PCB cleaning
Post by: Rob Strand on March 23, 2019, 02:02:58 AM
In general I'd say a tooth brush (soft bristle) is the most useful.  I do occasionally use ear buds and small stiff brushes for specific areas.   At work we have an alcohol dispensing bottle where we use quite a lot of liquid then some special "tough" wipes to wipe it off but we are only doing mods on development boards.

Title: Re: PCB cleaning
Post by: rankot on March 23, 2019, 05:12:17 AM
Thanks to both of you for hints! I'll try with a soft brush.
Title: Re: PCB cleaning
Post by: amptramp on March 23, 2019, 09:34:17 AM
We used to use brushes that were straight and relatively stiff to get all of the flux out.  I believe they were made specifically for this task.
Title: Re: PCB cleaning
Post by: duck_arse on March 23, 2019, 10:44:14 AM
Quote from: amptramp on March 23, 2019, 09:34:17 AM
We used to use brushes that were straight and relatively stiff to get all of the flux out.  I believe they were made specifically for this task.

get a 1" wide paintbrush, cut the bristles right down close to leave a 3 day growth length - stiff bristles, Bob's yer uncle.
Title: Re: PCB cleaning
Post by: bloxstompboxes on March 23, 2019, 11:22:45 AM
I've used hog's hair bristle brushes like these for years. They are used by electronics manufacturer's in their rework departments and are tough and ESD safe. They work great for cleaning off flux and won't hurt surface mount components either.

https://www.amazon.com/MG-Chemicals-Non-Abrasive-Cleaning-Bristles/dp/B004SPCXYO/ref=sr_1_4?hvadid=241922555907&hvdev=c&hvlocphy=9014691&hvnetw=g&hvpos=1o2&hvqmt=b&hvrand=1311542360234202382&hvtargid=aud-676677759484%3Akwd-48819510&keywords=hog+hair+brush&qid=1553354403&s=gateway&sr=8-4
Title: Re: PCB cleaning
Post by: davent on March 23, 2019, 12:29:44 PM
I've always used a dental pick to pop the hardened flux off then a chopped down bristle brush to remove the dust. Found board cleaning with solvents a pain to use, made a big mess unless i used copious amounts and they dissolved all my Sharpie notes i'd added to the board.
dave

Edit, i also spray a coat of lacquer on the trace side of the board to prevent copper oxidation and that gets dissolved away as well. Been a few years since i've done any electronics, rusty brain.
Title: Re: PCB cleaning
Post by: EBK on March 23, 2019, 01:37:41 PM
I use cotton swabs, which do get shredded, as you've noted.  I pick up the shredded cotton lint with blu tack.  I should probably adopt one of these other suggestions myself. 

I did notice, however, that my cotton didn't seem to be shredding quite as much once I started using flush cutters instead of diagonal cutters to snip leads (still shredding too quickly to be an ideal solution though).