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To prime or not to prime.

#1
I am painting my 72 corvette. It has the original paint and then it was painted once over it. The second job was nice but the car needed some cracks fixed. Block sanded the whole car got most of the second paint job off and it's nice and straight. I have a gallon of slick sand that I was going to prime the whole car and block it. Now that I have the car already sanded do I need to prime the whole car or just the areas of body work. I have SPI white epoxy I was going to put on after I sanded the primer.
 

Chris_Hamilton

Trying to be the best me, I can be
#2
Before you put the slick sand on and if it's close like you say try this, spray 3 coats of epoxy letting each coat flash at least one hour before the next coat. Set it in the sun if you can for a day (ideal) if not let it set a couple of days (always keeping temps above 65-70) and then block. If you need to repeat the same procedure and that should take care of it if the car is pretty close to start with. Poly primer builds so much I don't like recommending it. If the car doesn't need build then I wouldn't use it.
 

Barry

Paint Fanatic
Staff member
#3
I am painting my 72 corvette. It has the original paint and then it was painted once over it. The second job was nice but the car needed some cracks fixed. Block sanded the whole car got most of the second paint job off and it's nice and straight. I have a gallon of slick sand that I was going to prime the whole car and block it. Now that I have the car already sanded do I need to prime the whole car or just the areas of body work. I have SPI white epoxy I was going to put on after I sanded the primer.
Dont do it!!
That factory lacquer has to come off.
Epoxy will help some but can't save it.
Easier to finish taking off now with 80 grit day than after paint is piled on.
If your keeping car you will be stripping now or later.
 

Barry

Paint Fanatic
Staff member
#4
If you decide not to strip, do as chris said but again epoxy can only save you to a degree here.
What ever you do don't apply the poly right over the lacquer as it will cause wicking.

With an 80 grit da, if i start around 8 on a staurday, i can have outside of vette stripped by about 12.
And your allready ahead of me at this point.
 
#6
I should have worded the original better i don't know if it's the original paint or has been repainted the original color. It's no problem to strip it as I am close now.

Just went outside and hit some of the original color silver paint with laquar thinner. It didn't come off, must be a newer paint job.
 
Last edited:

jlcustomz

evil painter
#8
While it may initially look great going over old stuff, anyone with fiberglass experience knows how through constant hot & cold cycles, things just seem to gradually show up here & there even without an actual failure.
 
#9
Got the car half way stripped. Sanded most of it with the 80 grit. I bought some fiberglass paint remover to help out a little. I needed to speed up the process a little. I have used this product before and haven't had any problems. After it is all stripped I am going to spray the car with the slick sand and then will block it to make sure it is straight. Then the epoxy.
 
#10
If I'm not mistaken, if you have it stripped Barry and the others will advise to epoxy prime the bare glass first! Then bodywork over it. ...if I'm learning the process here correctly. But by all means hear from the others first.
 
#12
I agree with Slofut on the epoxy first, and would also add that thorough cleaning and drying of the fiberglass after stripper is the most important step on the whole job.
 
#13
If I'm not mistaken, if you have it stripped Barry and the others will advise to epoxy prime the bare glass first! Then bodywork over it. ...if I'm learning the process here correctly. But by all means hear from the others first.

Why would I put the epoxy first. It's a plastic car. I can understand the epoxy first on a steel car to prevent rust and then do the body work. I am not worrying about rust. I put down the featherfill and then block it. 90% of it will come off and then epoxy to seal it all up.
 
#14
I'm thinking it's to better bond to and seal the very porous fiberglass. And I'm just saying this because I remember a recent thread about corvettes and the recommended procedure on bare glass (here) was epoxy first to have the best base to start from. Maybe Barry will chime soon in case I'm all wrong on this.
That said, I had previous paint and no time to strip and ended up doing bodywork first, slick sand, and will put epoxy on to seal.
 

Barry

Paint Fanatic
Staff member
#17
Nothing wrong with the stripper as long as you use the proper one. I have been using it for the last 20 years with no problems.
If it works that is all that counts.
Did you know on that 72, you have 2 to 4 panels that are are SMC? (adhesion?)
Did you know the GM tech warning going back to the 60's say if stripper is used all bonding strips must be redone? Of course all shops that do vette restros always redo the bonding strips any way.
Did you know the SPI epoxy is air tight and 100% waterproof and when fully cured with proper mills its stronger than a gel coat?
Like I said its up to you and if it works continue on!
 
#19
I have used this without any problems KleanStrip GAF 354 and this and Captian Lees. Both are designed for fiberglass and never had any problem with either. I have also stripped them with razor blades and sanding.

Barry your epoxy is the best I have used. Every car I have painted in the last 8 years has had it on it. I have enough to do my 72 Vette waiting for me to finish stripping it.
 
#20
Thanks Goat,
I used to use Capt Lee's all the time. Didn't realize they still made it. It was my favorite, I'll have to find it on line. Razor blades are good on a corvette if you use them with care.
 
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