Red86Z51

THANKS to all who helped me out on my topic "Let's talk: PAINTGUNS" located here: http://forums.corvetteforum.com/show....php?t=1042958 As always, I got lot's of GREAT information from those who have "been there-done that"!

Now lets talk PRIMER COATS. I've been getting conflicting information on this topic. Let me start by telling you where I'm starting from: Completely bare fiberglass. This car has been media blasted. The media blasting has left "imperfections" on the entire area of the car where it cut into the body slightly. I'm working on filling what's deep enough to need filling, but the rest of the car has a rough texture to it.

Once the bodywork is finished, I have been told I need to shoot a coat of epoxy primer to "seal" the car, then shoot urethane filler primer and block sand smooth. I have also been told to shoot the sandable filler primer first, then the epoxy primer last....but wait, I have also been told to shoot a sandable epoxy primer, followed by the epoxy "seal coat" primer.

I'm confused

What has worked best for you guys???

bobs77vet

i have painted several steel bodied and aluminum cars....what i did was get the paint manual from the local paint shop....it listed all the manufactures paint products and the instructions to use them... i figured they knew best and i did not have to worry about paint compatibility issues if i followed their instructions and used one product line.....i think i had to pay for the instruction book like $19 or so....good luck...make sure before you spring for the book that it covers the fiberglass cars....

toyvet1

When I painted my car 3 years ago I went to the paint supply store and they answered all I needed to know. 3 years and no problems have popped up. Ask the people that know.

corvettejay

on bare glass their is only 2 things to spray first. either gel goat, or
a poly surfacer which is basically a sprayable resin. I use the sikkens brand I think called poly fill and their is one called feather fill. the stuff comes with a hardner in a tube just like the one used for fiberglass repair. you will need 2 quarts to put a couple of coats on the car. and this stuff sands hard. if you start to sand through stop sanding their, you will have to spot prime those spots if you
sand through

after spraying the car with that you can then use a
regular primer for the next prime and block. this sands way better, put 3 coats on, guide coat it and sand it.

jay

LFZ

my advice...spray Epoxy Primer first..seals the car, do your body work, spray primer surfacer, block sand and wet sand, then spray primer sealer before laying on color.

Roadster71

I also had my car media blasted and then sanded afterwards with 250 paper and sealing with epoxy. Next it was urethane primer surfacer.

sb69coupe

The epoxy primer will seal the bare glass strands, keeping them from causing any shrink in the paint after applied,

Shoot the epoxy primer, followed by the high build primer-surfacer. Block sand till you're blue in the face, then shoot the topcoats.

Oh yeah, make sure that you use all the products from a single manufacturer. That's the only way to guarantee compatibility and have the manufacture give any warranty for defects.

427V8

Gel coat??, it it still 1960?

I disagree, you don't need to 'seal in the fiberglass strands' they are already bound with the resin.

You want a sandable primer first thing to fill in all the holes left by the bead blasting. If it says non-sandable, it is believe me it don't sand, it just gums up the sand paper.

Get two contrasting colors, like gray and black. Spray the gray and sand it ALL off untill it looks perfect.

Then spray a light guide coat of the black and just barely sand it off with a long board. This will show you all of the low spots. Fill / fix the low spots and repeat untill it's perfect.

Also make sure the primer and everything is compatible with the system you are using. Do not mix systems unless you know what you are doing.
Epoxy primer will NOT save you!

I painted over an unknown primer _once_. I sealed it and used a 2 part epoxy primer. When I hit it with the second base coat it wrinkled up like a plastic bag in the fire. Had to strip it all off to the base.

Trust NOTHING.

GDaina

Feather Fill by Fiberglass Evercoat, been replaced by Slick Sand...I used Slick Sand on mine, great product...no need for any other primer. Slick Sand will fill all the imperfections....shoot a heavier coat, block sand with water and shoot a thinner coat, again block sand with water, if all is ok, then apply paint.

hunt4cleanair

Dave:

Nice series of paint queries.

Red86Z51

Thanks for the replys!!

I have also been told it ie VERY important to "seal" the fiberglass as media blasting wipes out the gel coat (which I see is true) and takes it down to bare glass. The bare glass is porus, and unless it's sealed, the paint will find pinholes, and continue to be sucked in like space into a wormhole, no matter how many coats of paint are shot.

It looks like the general concensus so far is to seal, fill, then paint. One thing everyone agrees on it using the one manufacturer for all paints, which I will definately do.

Please feel free to add favorite maufacturers and any other advice you think will help. Thanks!!

Dave

Roadster71

The folks at PPG recommended to seal with epoxy sealer regardless of how the paint was removed.
Also, I am pretty sure that c3's were never gel coated to start with.

Red86Z51

Thanks!! I hope this helps out others as well as myself


I am learning so much...this is great!

Now, for the gel coat, I didn't know that. What the media blasting did was remove the outer smooth layer on all of the panels (as you know since you did the same to yours as I did mine). Would this layer be a resin coat instead of a gel coat?

427V8

The sealer goes on after the primer and before the basecoat.

It reduces the effects of different kinds of paint / filler on the base coat. Without it you will see color changes where the filler is.

Take a paint class, they often have free ones at paint supply stores.
It's not rocket science if you just follow the manufactures directions and stay within a system.