Color sanding and buffing
 

I am going to paint my GMC with a single stage Urethane paint. I realize that color sanding and polishing will "cut" into the paint, as such, how many coats of paint will be required in order to not end up going to deep and exposing primer or metal?



Thank you...

Depends on how agressive of a color sanding your planning on. 3 coats is usually sufficiant enough if your just cutting down a little of the peel and the dirt nibs starting with 1500 or 2000 grit. But if your planning on getting a little crazy and start cutting with 1000 grit to acheive a flatter finish then you may run into trouble with sand throughs with only 3 coats especially near edges. It really depends on your expectations as to how fussy of a job your going to do. Anyway the more agressive your going to be you may need more material to sand into, roughly 4 or even 5 coats to be safe.

Makes good sense to me! Thank you!!!

I did a test once and found that if you do a nice cut and buff without getting crazy you only cut about 1/2 mil while two coats of high solids clear gives you about 2.5 mil. That extra coat is plenty as long as you don't cut too much off.

One of the tricks that I like to use is don't sand all the texture out with the coarser paper, bring it down close, but not all gone. When you switch to the next finer paper you are doing this to sand out all the scratches from the previous paper right? So why not leave a little of that texture and in removing the material that has the scratches from the previous paper you take it that little bit further removing all the texture. I feel much better doing this than removing all the texture THEN removing even more material to remove the scratches, get it? Try 1200 first, going down any coarser is often not needed and you are only removing material unnecessarily.

Brian

If it has metallic or pearl in it, you can get by with lightly scuffing over it, otherwise you will get into the metallic or pearl and really mess it up.

This is true if it were a single stage (SS) but if it's a BC/CC (Base Coat Clear Coat) cutting and buffing changes nothing other than making it's shine more brilliant.

Brian

I do recommend 4 coats, I start wth 1000 to 1200 grit cut the orange peel then go with 1500 t0 2000. Then use 3M buffing compound and finish with 3M finess-it II.