wet sanding

[nuthinseasy]

i am doing the cut and buff on a friends recent paint job. it was dupont base/clear, applied very heavily, lots of orange peel and a few fisheyes. starting with 1500 and a hard block, then 2000 on a 3m sponge, then buff with 3m perfect III, and i've done this many times, i have never seen sanding scratches so difficult to remove. even with minimal pressure, old paper, on and on. the paint was not baked, i think the painter was though, it is about 2 weeks old. am i missing sumpin?

[Ryan_Bihun89]

Re: wet sanding

maybe you should wait at least 30 days for the paint to fully cure. That way the clear will be less "wet" lets say, and would be more accepting the compounding.

Did you tried going to 3000 grit paper? Did you tried the Purple Foam wool pad with M105?

Let me know if i helped.

[Michael Stoops]

Re: wet sanding

Oh you want to talk about paint that's tough to buff out, huh? You should have been here with us last week doing a little sanding/buffing project on a BMW M3. Black. Of course. The word "challenge" comes to mind. Other words come to mind too.


Is all this sanding by hand or via air powered DA? If by hand you might want to step down to even 3000 grit with a foam backer to refine the scratch even further. Depending on all the variables can go into a respray, it just sounds like you're encountering some very hard paint indeed. Because of that, refining your sanding scratches as much as possible will really help out the compounding process.

A wool cutting pad like our W5000 double sided wool pad and some M105 on a rotary spinning at about 1800 rpm ought to pull out those sanding marks, even on very hard paint. Out of curiosity, are you using the 3M Perfect-it III 05936 or 05933? The 05936 is definitely more aggressive but seems to leave a less than pretty finish - which is fine if you know that going in and don't mind the extra steps needed to clean up after. M105 offers tremendous cut but also finishes out really nice, even with a wool cutting pad. That's not to say it finishes 100% hologram free, but it's usually a darn sight closer to that then most. Usually.

[nuthinseasy]

Re: wet sanding

i'll have to look at the P-3, check the part no. this is a black finish, with a wool wheel. i talked to a meguiar's phone rep the other day, and he recommended M-85, then M-83. local paint shop guy says to use a foam wheel for the 83, so tomorrow i try some more. and i have been soaking my sandpaper and it really seems to work

[Andrew C.]

Re: wet sanding

You could also try using M105 followed by M205