Primer over DP50 Epoxy?

'61 last year had PPG DP50 Epoxy primer (actually DP48White) over the stripped and phosh'd body. I just finished steel and filler repairs to quarters and recovered those with DP. I am ready to spray Omni 282 hi-build surfacer. I need to rough it up but does body need a fresh coat of the DP50 before the Hibuild 282?. DP Sheet suggests re-coat but is that for topcoat and primer?.

New to tinknockin'...
Thanks

 

My suggestion is to call the folks @ PPG.
Dave

 

you should be able to just scuff it with some scotchbright and spray the 282 over top of it.

 

If DP has sat more than 1 week, it should be sanded, cleaned, and recoated, regardless if your are priming or topcoating. Then needs towait 30-60 minutes for one coat and 60-90 mins. for two coats depending what hardner you use. I'll try to post a link to the tech sheet. PPG has an awesome site for looking up tech sheets for all there products. Good luck and wear a mask! I'm sure you already do
https://buyat.ppg.com/refinishProdu...roductID=50798ced-3499-4eb5-9787-2db7e520df08

 

After 72 hours you need to sand the Dp 50 or any Epoxy primer as it gets to hard. I like to put on three coats of DP on the bare metal and then do the filler work and finish the filler and Dp with 180 grit paper and then two coats of Dp and then three coats of High build wet on wet. Seals everything up and builds a surface that's easier to sand.

The Old Tinbasher

 

Can anyone tell me if you can spray DP50 over Zero Rust? I have some areas that got coated with the stuff while doing some rust repairs. I can scuff it up, but to remove it will be a pain. I will call the PPG rep but figured I would as here.

 

You can sand it and go surfacer. If you wish you could lay a sealer type coat over what you've sanded by reducing the DP. I don't care for DP over filler for any form of build or perhaps coverage. Filler over DP then DP over that same filler, has a tendancy to swell the edges of the filler due to the same family of solvents and binders permiating for a chemical bond. Even though there are similar solvents in surfacers those solvents purge faster so swelling is reduced or eliminated. Corrosion protection over filler shouldn't be needed anyway.