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Air compressor owners - Questions for you!

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ChadTower:

Yep, you can put game PCBs in the dishwasher if you want.  Just don't power them until your 100% certain it's dry.  The amount of moisture out of that spray gun shouldn't be enough to worry about there.  It's definitely safer than scrubbing the board.

NOTE:  every PCB layout is unique... know what is on the board before getting it wet.

MonMotha:

Almost all modern PCBs are washed in water or isopropyl alcohol to remove flux residue, especially that nasty flux that's needed for the crappy lead free solder you Europeans made us all use (sorry, had to say it :) ).  They are usually then air dried but are sometimes baked at ~75C to encourage the moisture to go away.

However, new PCBs usually use LPI soldermask.  This holds up to moisture well.  Older PCBs used other kinds of soldermask which can, in some cases, cause the mask to fall off due to the moisture getting under it.  I've never had this happen to me, but it can happen.  You're usually going to be fine, though.

Be sure to remove socketed chips since moisture will get stuck around those sockets, and let things dry at least overnight (better for a couple days) before using again.

Yes, you can actually usually use a dishwasher if you want, but it's kinda harsh (but very effective).  No detergent, turn off any extra heat during wash/rinse.  Heated dry at your option; I recommend air dry.  Keep the boards on the top rack.

As for air from an air compressor containing excessive moisture, I've never had a problem.  I clean computers all the time.  Heck, I do it while they're on sometimes, though that may be living a little dangerously.  I've never seen water come out of my blow gun, but the air isn't "dry", no.  A little water just isn't a big enough deal to care.  You can get air line dryers if you want.

protokatie:

As far as the "washing a pcb board in the dish washer thing", I would be very worried about any electrolytic capacitors on the board. Or any electronic component that uses paper (or similar) as an insulating layer. I would also worry about any POTs on the board as well, as any moisture that can get into them will make them act really screwy if they dry too slowly and allow for oxidation (random levels of resistance as the POT is turned).

As far as spraying a PCB with an air hose and getting a little moisture on it, I wouldn't worry.

I wonder if the use of isopropyl is mainly to act as a quick drying agent to prevent oxidation, or if they simply add components that can be easily harmed by submersion after the wash... ?

MonMotha:

If you don't use heated dry, electrolytic caps will probably be OK.  Lifetime might be degraded a bit.  They're usually good to at least 85C operating, and storage temps are usually a bit higher. They're also sealed pretty well.  Mechanical components are another issue, but if you have clean water (big if), you'll probably do alright.

I still tend to stick to the good old water or alcohol and a soft instrument such as a Q-Tip or maybe a toothbrush if things are really bad.

Alcohol is used because flux is quite soluble in it.  A follow-up step with water is usually performed to remove any residue that's left as the alcohol will remove bulk but can deposit a film over the entire board if allowed to dry since the flux will come out of solution as that happens.

SavannahLion:

Didn't we have this discussion about washing PCB's before?

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