Originally Posted by snydski
Build up of paint causes shelling or chipping I say Strip it . The use of toluene paint thinner will blister the clear coat after a few seconds, and then can be scraped off with razor blade , if you don't get it the first time do it again you will definitely feel the paint getting soft . It is less caustic than paint remover which will work , but might melt the plastic . Then take a heat gun to the decal or use the "Wonder Wheel" as seen on TV to remove the decal. Remove any residue with W-D 40 and wipe with denatured alcohol. I would use a "Two Part" catalyzed polyurethane and retarder with recommended thinner most likely methyl ethyl ketone , but not too thin this paint is made for .0003 mils a coat , , wet coats that are applied with a HVLP (High volume low pressure) sprayer which works well with smaller compressors and these paints don't need a clear coat but they must be mixed well and strained . If you live by a Marina these coating are used for boats and bath tubs and even tile the other stuff can be got at lowes. The mix that worked for me was 2 part base to 1 part catalyst and thinned 25% by volume not weight . paint takes hours to dry and 3 days to cure but it cures long after that.
I am sorry, but where do you get this stuff? Remove decals where you are going to paint with WD-40? Not anywhere anything I am painting! A wax and grease remover, a urethane reducer, even lacquer thinner but certainly not WD-40! HVLP gun works well with smaller compressors? HUH? High VOLUME
, small compressors don't have high volume, they have very LOW volume, HVLP needs a BIG compressor that produces HIGH volume.
Retarder? RETARDER, he is painting a tiny part that requires only a couple of passes a foot long, why in the world would you want a retarder?
I agree that a build up of paint causes easy chipping but we need to look at the "Bestest" way sometimes. Stripping plastic can really be a chore, it often results in marred up plastic that then needs to be primed and surfaced, building up material again. For a newbe, painting over the clear and decals may be the best way to go. But yeah, if one of these parts were stripped to see how it goes, you are right stripping is the best way to go. But if stripping that one panel gets you into trouble, maybe sanding and shooting is the way to go.
Even that "wonder wheel" is often too aggressive for a plastic part and will "grind" plastic away. A lot has to be thought about before stripping plastic with multi layers of paint and decal. It can be very difficult proving disastrous to a newbe.