Shooting primer

i want to put a new color primer over the existing primer. What should I do as prep before I shoot the new over the old?

Thanks

just sand all the old primer with 400 grit and over all bodywork just block it w 400 also then clean it and shoot it w the other primer

Edited: 2/26/2006 1:24:47 PM by bagged85

yea id block it w/ 320/400 grit till the old shows throught, blow it off tape it off, blow it off, tack it shoot it.

Edited: 2/26/2006 1:11:31 PM by fordOndubs

Sorry I'm new to all this body work, what do you mean by tack it?

im thinking he was talking about a tack cloth

ok thanks

I d block it with 220 grit wet and spray it

Block it with 320grit dry, then wet sand with 500 or 600 grit, blow it off, tack and spray. What kinda primer are you using?