Primers?

[69protour]

I'm almost ready to prime the underside and inside of the camaro. A good friend suggested using DP90 primer which is waterproof. Then on the underside I'm going to put the tintable undercoating on. Kinda like they did on Rides with the Cuda. Does anyone have any other primers they would suggest? Thanks guys. Trond

[CAMAROBOY69]

I have been extremely satisfied with the Epoxy primer (AKA DP90)I have used on all my vehicles.
Drove 2 straight days in the Power tour this year in severely heavy rain and there is still no sign of rust coming thru anywhere.

[WS6]

hope im not hi jacking the thread with this, but would DP90 also be a good a primer to use to keep from having everything cure only to have the sanding path exposed? i remember reading in a high performance pontiac that with some primers(hi build i believe) after six months or so when the paint and everything has fully cured you can have the sanding paths and imperfections that were covered up and smooth be exposed and visible under the paint.

[68protouring454]

that is only when using cheaper products, and or you rush topcoating it,it mostly occurs using urethane primer that is either cheap and or you top coat to soon,it needs to shrink (dry) completely before top coating,if not you will see bondo areas etc where the primer shrank into the sanding marks, dp90 should not do that as it is more of a weather barrier than any thing, its the highbuild urethane primers mostly,you should let the cheaper ones set at least a week in above 60 degree weather, (hardners do not work below 58-60,even the best primers should sit a day or be baked.
the reason only the bondo spots show is because you sanded the area with 80 grit and finished with 180 then primed where as all other places should be sanded out to 400-600 grit,but even though you sanded the primer over the bodywork with400-600,it still has those deep grooves that it shrinks into, very important to let the primer cure.
jake

[BRIAN]

DP is a good choice just be sure that the metal is clean as possible hitting it several times with prep solvent. You will be surprised what comes off. They make 2 activators and I just cant remember which is which but anyway get the one that takes approx 30min to set up as it sticks a lot better. As far as sand scratch swelling it can happen with the best of primers. There are a whole list of things that can cause them. If you are going the DP route use it straight through. Use dp on the bare metal than k36 than seal with dp before final color. Actually DP is a great sealer which works great on fiberglass cars as final seal coat. SEM makes agood bed liner that is tintable. Honestly I would try ncp275 which is an etch filler especially if you are going to coat anyway. Cuts down on amount of products. Good luck!!

[68protouring454]

the only time scratches swell is when rushing top coating, imho i would not use a epoxy primer as a sealer, but i am sure it can be used for that, in a resto i strip/blast car then epoxy prime or etch prime depending on car and timeline, then urethane prime, block sand 2-3 times and paint, i finish urethane in usually 600, even 800 if the color has lots of pearl and metallic in it, goodluck
jake

[WS6]

ok ill get back to yall on all this so i can do it right. i worked in a body shop for one summer. thought i handled the paint gun pretty well. im sure i have lots to learn, but i have the desire to paint my 79 when the time comes. i know ill prime it for sure. would also like to do the body work, which means panel replacement.

is PPG still considered good stuff?