Polyester Primers

The amount of poly prime depends on how well the plastic work or metal work was done.A good rule is to prime until you have no major break through.Then use a good 2k to shell over the poly and finish sand with block or stick.You can finish your 2k in 400 as long as you are sealing with 2 coats min.I try not to use no more than one wet coat.600 hand sand for solid colors and 800 plus for metallics.DA you can cut that back a little but,don,t machine sand a custom overall.