Circuit Board cleaning

[mike49504]

Is there anything out there that works better the acetone to clean circuit boards?

I tryed acetone on the board where the fets blew and it didnt touch the stuff.

I just wanna make the board look new again.

[jcx]

acetone is somewhat risky - many plastics craze or swell with ketones - isopropyl alcohol is more often recommended

also good is just plain detergent and water - at least where you don't have open case switches or pots

follow up with deionized water then alcohol

[Perry Babin]

If acetone didn't remove it, the solder mask was likely burned and the discoloration is permanent. I've used acetone for 25+ years and it's probably the best for cleaning soot from the board. It, however, will not remove residue from sugary drinks (coffee, soft drinks, etc...).

[Boofers]

Check out the MG Chemicals site for info - Electronic Cleaners

I generally use the 404 Contact Cleaner on everything.

[jcx]

you've been lucky - polycarbonate dies instantly on exposure to ketones, polystyrene dosn't like them either - don't use ketone solvents on any board with uncased clear plastic caps

[AEIOU]

Originally Posted by jcx

acetone is somewhat risky - many plastics craze or swell with ketones - isopropyl alcohol is more often recommended

also good is just plain detergent and water - at least where you don't have open case switches or pots

follow up with deionized water then alcohol

Yep, plain ole water works very good and a little bit of dishwashing detergent if needed. I've water washed all sorts of electrical and electronics, not moving parts of course, but circuit boards, even PC motherboards. Years ago I worked on electronics for the tomato industry and some of it was for farm/field use. If something went wrong, the whole unit would fill up with field dirt! Yes, I'd have to disassemble the entire unit and water wash everything.
If something has moving parts, like a keyboard or mouse, I'll disassemble it first. The real trick though is getting everything dry and I have a compressor for that. Anywhere water can get in, so can air. As long as you can dry whatever you get wet, you'll be OK. Like today I disassembled and washed a VCR remote control. The batteries leaked and messed up the battery compartment. I soaked the battery compartment in household vinegar to neutralize the "alkaline" from the batteries and then I water washed and compressed air dried the whole thing, piece by piece. I put it all back together, installed fresh batteries and it's as good as new.

[Perry Babin]

In 25 years, I have never seen any damage to any circuit board when acetone was used to clean soot from them. Unless I'm mistaken, he's trying to remove the damage/soot left by failed FETs. It's true that acetone is not safe for many plastics but the plastics used for most components in most car amps aren't harmed by it. The plastics most commonly damaged by acetone are those used for cosmetic components (display lenses, display panels, knobs, some powder coatings. etc).

Water does nothing to clean the soot left by failed FETs and it can take days to dry if compressed air isn't used to force it from under large caps and other large components.

Water does work well to clean dirty boards. Many people put the boards in a dishwasher. I've used a pressure washer many times. Removing the potentiometers is best.

[boxcustom]

Use the cheapest spray carb cleaner you can purchase. Works great and it is pressurized.
A friend of mine who was on the design team on the Orion HCCA series of amplifiers in Phoenix uses autozone carb cleaner.
It always works and is cheap.

[AEIOU]

Originally Posted by Perry Babin

In 25 years, I have never seen any damage to any circuit board when acetone was used to clean soot from them. Unless I'm mistaken, he's trying to remove the damage/soot left by failed FETs. It's true that acetone is not safe for many plastics but the plastics used for most components in most car amps aren't harmed by it. The plastics most commonly damaged by acetone are those used for cosmetic components (display lenses, display panels, knobs, some powder coatings. etc).

Water does nothing to clean the soot left by failed FETs and it can take days to dry if compressed air isn't used to force it from under large caps and other large components.

Water does work well to clean dirty boards. Many people put the boards in a dishwasher. I've used a pressure washer many times. Removing the potentiometers is best.

Only thing with using solvents on circuit boards and their components, anything as strong as acetone will remove all the inks and paint markings and sometimes even the silk screen on the PCB.

[Perry Babin]

The only markings that I've seen it remove easily are the printed markings on film capacitors potted in rectangular plastic cases. It can remove color bands from resistors and the silkscreen from the board but it generally takes a bit of scrubbing.

Carb and brake cleaners (I've heard of some people using this) often contain chlorinated solvents. If they do, they're significantly more dangerous than acetone.

To clarify, I don't recommend flooding the board with acetone or soaking the board in a vat of acetone. I use cotton swabs for cleaning around resistors and transformer windings when the FETs fail. For larger areas, I use a toothbrush but I'm careful not to let it get on any sensitive components.

Acetone is safe and effective when used with a bit of common sense.