Clean APCP residue from electronics?

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Jan 14, 2009
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I had a M1297 Cato that breached the avionics bay. The altimeters and BeelineGPS might be OK but they're pretty soaked in APCP residue. Anybody have words of wisodm on cleaning that stuff off? Thanks in advance!
If they aren't conformal coated it is going to be a problem as there are lots of spots for the residue to hide in.

It used to be rare for rocket electronics to be conformal coated but the last one I bought (ALT15KWD) was, so that might be changing. If you are lucky enough to have a can of the stuff you can do it yourself. I found one at Fry's Electronics. Of course it doesn't help now. :)

The residue is most likely water soluble but the catch is that the water will combine with it to make acid. Not a good idea. Try isopropal or denatured alcohol. Do not use rubbing alcohol as it has oil of wintergreen added. Be careful about pressure sensors. Pressure sensors have their own protective coatings inside the case so tape over the port to protect it while cleaning.

I had this problem with a GWiz LC Deluxe a while back and it cleaned up pretty well although I had applied a conformal coating before flight.
Had a similar problem myself.....a quick call t Jim Amos at missleworks resulted in the following advice.

Altimeters can be cleaned with distilled water or any clean water that won't leave hard water residue. Rinse off the altimeter and shake off the excess. Place in the sun or on a dash of car with the windows up to retain the heat and let thoroughly dry. Of course remove the batteries! Also the electronics cleaner in a spray can will also do. Try to cover the hole in the sensor if at all possible, but it's not mandatory. The key is to make sure it's dry, before firing it up again.

I had one covered in BP residue and another that went to the bottom of a pond. after cleaning they both worked fine. One was a Perfectflite and the other a Missleworks.

Hope this helps.

PS you should not put the sensor in direct sunlight though, make sure it's on the bottom if alt. is in direct sunlight for any length of time
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