Electronics > Projects, Designs, and Technical Stuff

Cleaning PCBs

(1/7) > >>

Sky_hawk:
I have some hand soldered PCBs I want to clean up, I tried to remove the rasin and other sticky stuff of  the PCB using alcohol 96%, and Chemtronics Flux-Off VZ, but neither is working very well. After using the Chemtronics Flux-Off VZ, it seems now there is a sortof white filmly layer on the PCB :(

What is the best way to clean them properly. I tried using Aceton on a old board, but aside from the risk of dissolving the silkscreen, it did not seem to the work well either.

Greetings,

Jan

Rerouter:
to be fair you didnt say the age / vintage of the pcb, when you get past 20 years, it always gets harder to clean, as the masking and silkscreen start degrading to a level where most cleaning products strong enough to lift flux start lifting them aswell,

i suppose if you dont end up finding anything, on some 30+ year boards, i have scrathed off the flux with a metal scribe and used some other lighter cleaner to tidy it up, but that gets into the region of how badly you want it to look nice,

Psi:
Be careful getting any pre-made circuit board cleaner on your skin.
I accidentally sprayed my hand while holding a pcb and my skin turned red in that area for 2 months.

I dunno what it has in it, but it's not good for you.

IanB:
You can use 96% ethanol, or methanol, or isopropyl alcohol. You need to apply the solvent liberally and use a stiff bristled brush to work the flux loose before rinsing it away. It won't just dissolve all by itself, it needs a bit of help.

Oh, and as Psi said, wear rubber gloves to protect your skin.

TerminalJack505:
Is the resin that remains due to a liquid flux you are using or is it the solder's core?  You might have to switch to a different flux and/or a different solder.

I use a so-called water soluble flux which is really easy to clean.  Some of the solder I use has a rosin core which is a little tougher to clean.  When I can, I use the water soluble flux and a solder that has no core.  I can clean a board up using just water when I do this.

Just for the record, once I'm finished soldering with a rosin core solder, I use isopropyl alcohol and an old toothbrush to clean the board.  (Yes, I should be using an ESD safe, $50 brush.  blah, blah, blah...)  I dip the brush in the alcohol and scrub the board 'liberally', as Ian says.  I then rinse the board under running water (just so long as there are no components that will have an issue with that.)  A second cleaning is sometimes necessary.

After wiping off the excess water with a paper towel I then I use an old hair dryer or my hot air station to dry the board.

Navigation

[0] Message Index

[#] Next page