[cutthroatkid]

Really need help.My paint laid great unfortunately I learned the hardway that I need better lighting.Well I in a few spots got some bad scratches under paint so I need to ask some questions&really need some help.Then I think for the most part Ill be good to go.
Ok what is the difference from p grating I need some 400 but I have been buying all of my materials &they don't have 400 only p400. Also what do you use to just scuff&shoot like
on a trailer..still gonna primer but don't wanna sand to much..and any idea where to get 6 in 400 discs in bulk ?

 

[sunsetdart]

First thing is you should never use a machine with discs to remove scratches. All you will do is create many more problems.
To remove scratches you start with a coarser paper like 220 wet, then move to 320, then 400. You should also be using a sanding block to make sure the surface stays flat. You sand the area east to west with 220, then north to south with the 320 then go diagonally with the 400. This way you get the area smooth and flat.
Is this alot of work.................yes........but a paint job is all about the right preparation. You can be the best painter in the world, but if the prep is shoddy the paint will show it right away.

 

[jcclark]

Most all the papers are the "P" series now.
400 is fine to shoot over, 600 is a lot safer when spraying
metallics, it'll cover easier if you don't get enough paint on it.
But P400 is what most paint over.

go here for a grit chart
http://www.hotrodders.com/forum/sandpaper-grading-grit-charts-79541.html

 

[cutthroatkid]

Thanks guys I'm trying to find some 400&600 discs

 

[mike the painter]

You shold be able to get 4-600 DA paper at any body supply store...For a trailer the red scuff pads work pretty well...
if you want to eliminate any scratches in the future you should use a coat or two of primer if you and with anything coarser than 400 wet or 320 DA,so lets say you blocked out the car with 180 ,you wont be able to get the scratches out by just sanding again with 400,you'll need to prime and sand again with 400 or 320 da ...When I wet block with 400 I always give it a breeze over with wet 600 ...dont for get your guide coat...

 

[MARTINSR]

I have found 3M powder guidecoat is the best for those fine scratches for me.

Don't jump from 180 more than 240 or 320 tops. You can sand out 180 with 240 then 320 then 400 if you had enough material and if you guide coated it so you could see them. But as Jim pointed out, realistically, why? 180 is something you use before you prime, to CUT something FLAT. So once you have CUT it FLAT, apply a few coats of primer then with this new FLAT surface you can sand with a finer paper being you aren't needing to CUT it FLAT being it already IS flat.

Brian