Block Sanding Sequence

FNG, has a question. I am building a a 47 Plymouth Sedan, stock on the outside retro under the skin. Flathead, bored, cam, ported, decked and blocked, dual carb and exhaust. Here is what I have done so far, 1. Stripped to bare metal sanded and cleaned. Sealed it with Nason 491-17 etching primers, lightly blocked it with 180 dry, Three wet coats of Nason 421-19 2K Ure Primer, guide coat, blocke 180 to 220, reshot it with three more coats, guide coat sanded with 320 to 400. I have all of the pieces to 400 ( took the doors, fenders, hood and trunk lid off) Now should i spray a light coat of primer then sand with 500-600 or can I just keep sanding with 500-600 making sure I do not cut to metal? Also, should I sand it wet or dry?

 

Depends on the paint you are using. Oldder style enamels, and single stage, you can realistically cut with 320-400 and then shoot. Lacquers were 400, modern base clear, Dupont usually I cut with 400 or 500 and shoot. PPG seems to still show sctatches with 500 so I go to 600. Metallics and pearls usually need a finer finish, as well.
After my 180 cut I usually start wetsanding. Unless it's a quick, small touch up sand, then I might do it dry.
But ask 10 different painters, you'll get 10 different responses.

 

IMO--That's about right.
if you're doing a silver or high metallic basecoat color, you'll want a 500 scratch or finer. Straight enamel/Straight urethane's are pretty forgiving, but i wouldn't go below 400 even with single stage solid color Urethane.

 

Thats what I was thinking, though should I keep sanding or should I shoot another coat of primer?

 

Wetsanding will give the best results by far.
You'll probably have to either seal the panels- or apply another coat of urethane primer then sand them. You shouldn't have to sand the sealer...so- which do you WANT to do?


Also- what are you painting-- material/color?

 

Try guidecoating again and wet sand it out if you have enough primer on there and its how you like it. Less is more. If its a metallic id go 800, but im just one of the 10.

 

i get away with 320 da dry or 400 wet for metallics, but i always use a sealer.

 

sounds like you got plenty of primer on there already. i would 600 wet and shoot it. if you go through with the 600 seal it first. good luck.

 

I would either go 320-400 wet and seal, or 600 wet and shoot. But Mark pretty much hit it on the head there, not much more you can add, except my opinion of course.

 

Has anybody used one of these, on the flat panels,or should I stick with manual labor