Is this normal? And is this ok?

enkeivette

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Mar 30, 2008
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To have high spots and low spots like that? I swear I'm pressing the power sander down at the center and this is still happening.

awdbbn.jpg

And I have another question about what layer I need to take it down to. My car appears to have:

A layer of electric blue,
A layer of dark blue,
A layer of yellow something??? Primer? Sealer?
A layer of gray primer
At least one layer of white stuff. I assume it's the gel coat, and underneath that is the dark brown, which I assume is bare glass.

So here's the question. Do I need to get rid of the yellow stuff completely? I mean as long as the surface is smooth (white and yellow) would that be ok to primer over?


Also, if I may vent. There is bondo on my car, some of which I blasted off with my pressure washer. (That's how I removed most of the paint) Who puts bondo on glass? Who? Why? Use glass! It's so easy!
 
To have high spots and low spots like that? I swear I'm pressing the power sander down at the center and this is still happening.

awdbbn.jpg

And I have another question about what layer I need to take it down to. My car appears to have:

A layer of electric blue,
A layer of dark blue,
A layer of yellow something??? Primer? Sealer?
A layer of gray primer
At least one layer of white stuff. I assume it's the gel coat, and underneath that is the dark brown, which I assume is bare glass.

So here's the question. Do I need to get rid of the yellow stuff completely? I mean as long as the surface is smooth (white and yellow) would that be ok to primer over?


Also, if I may vent. There is bondo on my car, some of which I blasted off with my pressure washer. (That's how I removed most of the paint) Who puts bondo on glass? Who? Why? Use glass! It's so easy!

I'd remove all of the paint on the entire car, but that's just me. Corvettes didn't come with gelcoat.

There is nothing wrong with body filler IF it is used correctly. You also need to use the correct filler for the body...regular bondo brand is crap and isn't formulated for fiberglass use. Body filler gets a bad rap because there are people out there that use it the wrong way. Use as little body filler as possible on the entire car.
 
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I'd remove all of the paint on the entire car, but that's just me. Corvettes didn't come with gelcoat.

There is nothing wrong with body filler IF it is used correctly. You also need to use the correct filler for the body...regular bondo brand is crap and isn't formulated for fiberglass use. Body filler gets a bad rap because there are people out there that use it the wrong way. Use as little body filler as possible on the entire car.

What's the white layer if it's not a gel coat?
 
I assume the white, gray and yellow is primer. However watch out, the original fiberglas has a gray marble looking color to.

I removed all of the paint on my car because that was what all the painters adviced. They were fearing problems with a reaction of the new paint to the old layers. At the very least you would have to isolate the old paint with some coat. However excessive paint buildup is often a problem, so I would take it all off.

If you take it down to the bare fiberglas, they adviced me also to isolate the fiberglas. You need an epoxy product for this (smc is epoxy based) because of the sanding you will have the original products in the glas that were used to release the panels from the mold coming out again and creating problems with the paint.
Be aware that some epoxies become hard as hell. This is not good either. It could create landscaping (don't know if that was the right term). Spies Hecker had a great product for this, namely their surfacer 0450 but it is no longer made. You could sand it like a primer, it was both a sealer and primer on epoxy basis.

As far as the high spots : with an electric or air sander, you will not now if it is really a high spot or to high of a pressure on your sander. I only use a sander to remove the paint as much as possible. Whenever I see the primer coming through I stop and block sand the rest. When the paint is all off, use guide coat all over, sand it lightly with a block (as large as possible in respect to the curves etc) and see where the high and low spots are. Fill them and sand them again with guide coat, when all this is done, the primer work with respective guide coats starts...(stage i'm in now)

Hope this clarifies some. Smyda probably is the most knowledgable person regarding body work here.
 
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Oh and remove that gasfill cap before sanding ... and all of the rest of the mouldings etc on the car. Preferably remove the bumpers also. Basically you would have to dismantly a lot of parts for a great paint job. On my car for instance I had paint coming of at the corners of the rear window, because it was never taken out. And edged is forming under there and since it is not always possible to degrease in there, you could have paint coming loose.
 
sanding or chemical stripping of old paint is so damn much work, i'm starting to wonder why not just replace the whole body with aftermarket parts and start fresh.


gkull said he saved 150 pounds with an aftermarket one piece front end. I don't believe him, but do acknowledge it may be somewhat lighter.

if you are a perfectionist, i gurantee no matter how much work you put in to this job, you won't be satisfied.

a power sander is going to make that surface wavy as hell. Stop what you're doing and chemical strip or hand sand with one of those blocking sanders.

http://www.vettemod.com/forum/showthread.php?t=529
 
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Sand or strip it down to the brown - that's the SMC. All other "stuff" might or might not be compatible with modern urethane primers (or epoxy)... I started with urethane primer over the brown surface that I sanded with 80 grit for good 'mechanical grip'. You will still see the 80 grit sanding scratches thru the primer, they disappear after sanding with 220 grit and two more coats primer.

I painted my '79 at home, now two years later it's still looking good.... nothing flaked off and there are no blisters. It's not perfect but way better than what I expected from a cheap garage job :1st:

Turtle: I think he meant 150lbs incl the vacuum tank and other stuff he removed, the hood is also a lot lighter than the stock hood... I think 150lbs weight reduction for the entire front conversion is reasonable.
 
Turtle: I think he meant 150lbs incl the vacuum tank and other stuff he removed, the hood is also a lot lighter than the stock hood... I think 150lbs weight reduction for the entire front conversion is reasonable.

if that's the case it might be worth shitcanning the stock front end.

Someone would have to tell us how many hours are involved in that then compare it to the time to strip or block out the existing stuff.

Brown stuff is SMC? i disagree. Its a very light grey. That brown stuff is primer of some sort i bet.

if he uses a primer/sealer he can put it over anything, so the other option is just sand until smooth using all those layers as a guide coats, don't worry about what colors are popping through and seal it off from the new paint. He's going to kill himself trying to sand all them coats off.
 
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I'll agree with all , only one hinted at block sanding, Large areas should be sanded with a sanding file to insure a flat surface, smaller areas done with a 4 x 4 " rubber block. Blocking will keep the surface straight and not produce cupping, Unless your over agressive. Talking with a local professional body man will bring a wealth of knowledge.

Note, seeing what your doing now, you are destroying the contour and flat surface of the car . You do need professional advice. and a couple lessions on sanding.

These remarks are not intended to be demeaning.
 
Turtle, damn you're pessimistic. And you can remove the vacuum tank & braces without using an aftermarket front end. I did it! And even if you could save 150lbs with an aftermarket clip, it's not worth it. At least not for anyone other than hardcore racers, like TT or maybe gkull. Think about it, what are you going to spend? 2K to save 150 lbs? Sh*t, buy a supercharger for that much, you'll be all over the track but you'll get faster lap times than had you made your car 150lbs lighter for sure.

Cherry, yes, I do need a lesson. Any volunteers? BTW what you see in the picture was after the first five minutes of me using the sander, for the first time! I've gotten much better aleady, I'll post more pics when I'm home.
 
enkei, use the sander wisely and you will be ok. But certainly block sand the thing.

If weight is a concern look elsewhere. The heaviest thing by far is the birdcage. Build one alu if you want to reduce weight. Next would be the front an rear bumper metal structure, either aluminum or carbon will do nicely. Next engine,driveline. Every lifted a diff ? Maybe an aluminum one, but then again they are not that strong.
 
Discarding the original glas because of the paint is foolish.

not if you're a racer and you are able to shed 50-100 pounds.

remember an aluminum block is $4000 and saves about 60 pounds.

its at least worth considering at this point, since he has 6 coats of crap to get rid of.

I want someone to trade me for my front clip and the brackets and all the other stuff

I want an after market 1969 front clip
 
Turtle is right, there is brown primer. I sanded/scraped that off, it's been so long that I already forgot. Here's an old pic:
100_1741Small.jpg

BTW, with the razor blade you can take 4-5 coats off at once.....
 
I think the white coat might be the original paint job then...

BTW, I've removed everything up to the white coat on 90% of the car with chem stripper and a pressure washer already.
 
What color code do you have on your trim tag? That'll tell you what the original color was.
 
stinger12;10026. ...regular bondo brand is crap and isn't formulated for fiberglass use. Body filler gets a bad rap because there are people out there that use it the wrong way. Use as little body filler as possible on the entire car.[/QUOTE said:
gee, I have "regular bondo" on my car for 12 years now without a crack.....I believe bondo is a polyester and fiberglass is a polyester, making them compatible.....................
 
Are you using a air sanding file or a manual sanding file. Anything other ""will make pockets in the surface. Its kind of hard to teach sanding here, one would have to write a book.
 
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