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Mon Mar 08, 2004 9:06 pm

I'm getting close to base coat-clearcoat. The car is covered in K36 and I'm starting to sand some guide coat, filling low spots with glaze, etc.

What's the best grit to use before painting? I'm not going metallic. It will be Albert blue (L50E) and DBC by PPG.

Some recommend 400 grit whereas some say to use 600 grit before shooting the B/C.

Does it make a difference for what I've got planned? :?

Mon Mar 08, 2004 10:22 pm

hey, 400 grit is great if you are first spraying sealer... 600 grit is perfect for a base-first coat, but I would make sure that the surface is very very clean and free of any imperfections that a sealer coat would eliminate. Have fun :)

Mon Mar 08, 2004 10:54 pm

Remember that all paints shrink a little when all the solvents evaporate.So the finer the better.So I would use 600.

Tue Mar 09, 2004 6:33 am

What about sealers?

If I sand the K36 down to 600 and then seal it with DPLF. Do I sand the sealer with 600 too, or does one not sand sealer?

Would it make sense to sand K36 with 400 then seal with DPLF and sand that with 600?

Also, do I have to sand primer/sealer stepwise (i.e. can I go straight to 600 or do I need to do it first with 400 followed by 600?)
Thanks

Tue Mar 09, 2004 9:29 am

Sealers are part of a wet on wet system, so no do not sand your sealer. Let it flash appropriately and apply base.

Sun Mar 14, 2004 5:34 pm

when i painted my first car once i had the finish smooth and perfect i went all the way down to a 2000 wet and dry paper, using it with soapy water, i guess it depends on if you want sand grain showing or if your top coats are good at hinding and building up

Wed Mar 17, 2004 5:13 pm

So, if I decide to sand the K36 with 600 grit. Do I need to go with 400 first or will 600 work right away? What will be less work:
A) 400 then 600
B) 600

Wed Mar 17, 2004 8:08 pm

Every painter i have ever met has a different way they like to prep. Personally when I has painting I guide coated and blocked with 320 wet, guide coated then 400 with a hand pad and if necessary guide coat and 600. This is assuming the car is pretty straight to start with.

Wed Mar 17, 2004 10:10 pm

I personally would never go any finer than 400 before bc/cc. You have to have enough "tooth" for the paint to adhere to. I have heard to many horror stories about paint peeling off because of too fine a paper being used pefore paint. Just my $.02

Fri Mar 19, 2004 3:17 pm

buguy is right you can't get too fine or the topcoat won't stick. I use 400 grit wet sanded with a block. Just make sure your paper is not a p-graded paper.