Alright, after hours of reading of posts and threads, I am even more confused. Different people are telling me different things...that Chevrolet started using SMC panels after 1982, or that they began using SMC after 1973; every post is different. I want to settle this once and for all so I can just buy the right materials and begin fixing up my body Below is a picture of a panel on my 1976 Corvette, which has been stripped down to the bare fiberglass.

Is this SMC or regular fiberglass?


If this is SMC, Then I will be using either Epoxy resin or Evercoat SMC Resin. If it is regular fiberglass, then I will be using polyester resin.

 

You shouldn't use polyester after approx 72-73.

If you want to play it really safe and are new to this then just use the West System Epoxy You get 2 cans and push dispensers for each can. You cannot screw up the mixture. It is a real epoxy and will stick very well to smc prepped with 24 grit

http://www.westsystem.com/

Lots of info on this site.
You can even make your own epoxy bondo with it.
Or your own panel adhesive.
Used it for years. Works great.

 

To answer your question, smc has a smooth marbled finish on both sides. evercoat smc repair with matt works very well just make shure it is fresh stock. Mix it exact and use a timer so you know when to stop. best of luck with your project, mur

 

Actually, GM started using SMC in 1966 on relativly flat surface panels like the hood. By 76, all panels were SMC
See the following thread;

http://forums.corvetteforum.com/show....php?t=1623228

Bullshark

 

'70 and older, all press molded.
Most '71 rear fenders are SMC; remainder of the panels are press molded.
'72 on, SMC.

If you feel you may have a mix of press molded and SMC panels, buy a bonding adhesive designed to hold both and you should be okay.

 

That grey is definately an SMC panel.

 

Mike, take a look at the articles I refererenced in the other thread I pointed to above. Both state that SMC was first used in 66. My GM 69 L-88 hood was built by Rockwell, because I remember thier attached manufacturing label when we purchased it way back in 70/71. Rockwell used SMC. Both my 70's also have SMC original panels. You been studying up on those NCRS manuals again According to them I need to change my original chrome shift **** to black chrome

Bullshark

 

That's what I was waiting to hear. I wasn't sure if they made an adhesive that stuck to both.

I'll soon be joining a large hand laminated panel to my SMC on my '76, and was starting to wonder just how I was going to do it, short of pop rivets.
John

 

Studying up?! Alla time.

His question conerned his '76. Should be SMC on the '76, unless panels were replaced by a PO.

 

bump...anymore input?

 

Just double-check that the Evercoat product is Epoxy-based and not Polyester. I used polyester based resin by a major mfg that had large text in no less than 3 places on the can indicating it was "compatible, " "Perfect" and "safe" for SMC fiberglass repair. Didn't stick at all. Mixture was right on. I've read other things to the same effect by guys in other posts. I didn't believe them until I saw it with my own eyes. The epoxy isn't hard to work with. There's no mystery. It is the same as using regular fiberglass resin, just a different product. The one notable thing is that the Ecklers Epoxy seems to give more working time till it 'hardens' than regular fiberglass resin, which to me is a bonus.

The other thing is I would advise to get a fiberglass roller (Ecklers # 10720). It's the way to go. I did glass work for years just laying it on till I used the roller. I wouldn't go back. Besides squeezing the resin in/out of the mat (more mat, less resin), it's a lot less messy to work with.

What I do is mix up a small amount in a paper cup. Then I use a regular teaspoon to daub it onto the prepared area and smear around. Then lay on my piece/s of fiberglass (that I already have pre-cut) and roll it out. Give it a while to "wet-out" the glass. Add another piece if need be and roll that out. After about 2 layers of mat, usually need a little more epoxy, so I spoon on a little more and smear about, then roll - and so on until the desired thickness is achieved.

I assume you know that if you use fiberglass cloth as you top layer, or it is exposed due to sanding down to it, you'll get a nice checkerboard appearance some time down the road. Cloth is stronger but use random strand mat for the top layers.

Also, according to a tech guy from a mfgr of epoxy resin, some mat contains styrene and won't incorporate correctly. I thought that was wierd, but I didn't have any problems with the Ecklers product (by Adtech).

...and don't forget to bundle up and wear a dust mask. Good luck.

Mark G