Sanding process?

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#1

what should i start sanding with? what grits should i use before i apply clear coat?

#2

good thing I looked around before posting, I to am curious to know what is the best grit to go up to prior to applying automotive clear coat. True nothing a little T&E wouldn’t be able to answer but I’m wondering what the general consensius is. thanks

P.S. Evan great forum :smiley:

#3

Thanks.

Here is what we do here at the shop. Other people might tell you differently but I find that this works for me.

If your surface is nice and smooth already and you do not need to do any fixes then start with 600 wet to 800 wet to 1000 wet to 1500 wet. After the clear coat has been applied and fully cured, wet sand with 1000 and then buff and polish.

If you have an irregular surface then you’ll have to go 150 or 220 dry to 320 dry to 400 wet and then 800 and so forth. I would not use anything less than 150 because you will not be able to get rid of the scratches.

Evan

#4

wow so you go all the way up to 1500 grit before applying clear huh?

#5

Yeah, but you can get away with just 1000 if you do it correctly.

#6

I go as low as 100 if I really screw up a surface.

However, I usually go with 220, 320, 600, and 800 wet.

Then 1000 and 1500 wet prior to applying clear coat.

I’ll use 3M rubbing compound, 1500, and 2000 wet if I need to clean up the clear coat finish.

BTW, it helps if you get a wet sanding stone (1500 or 2000) if you need to smooth out drips and runs on the clear.

Finally, I finish off with 3M Finesse-It II and then some polish (Zaino or Gel-Gloss). :smiley:

#7

There ya go. Vince got all the right stuff.

BTW, that 3M stuff is not cheap.

#8

Yeah, you’re not kidding…3M stuff is pricey.

I order it here: http://www.levineautoparts.com/comandglaz.html

…or I buy it locally if I need it right away.

#9

What should/can I use to wipe down the surface before I apply the clear coat?

#10

I use Simple Green cleaner and then rinse it off with water and let it dry.

#11

I have everything papered up and taped off ready to spray and wanted to wipe down the poly-lam surface making as little mess as possible before I spray on some clear gelcoat. Is it OK to use acetone or will that cause a problem?

Thanks…