Gelcoat Removal

[Jim D.]

My 66 corvette appears to have a dark gray layer that I think is gelcoat. How can I remove the gelcoat?

[Jim D.]

Re: Gelcoat Removal

The dark gray is probably the factory primer. GM didn't use gel coat.

[Jim S.]

Re: Gelcoat Removal

The dark gray is probably the factory primer. GM didn't use gel coat.

Jim , Sounds like a repaint . Didn't GM use red oxide primer in 66 ?

Jim

[Jim D.]

Re: Gelcoat Removal

This car was repainted back in the 80's a non original color, I think the dark gray is gelcoat.

[Russ S.]

Re: Gelcoat Removal

GM used red primer nor grey in 66

The dark gray is probably the factory primer. GM didn't use gel coat.

[Jim D.]

Re: Gelcoat Removal

GM used red primer nor grey in 66

My mistake. I know they used red on my 65 but I thought they possibly changed colors at some point. Regardless, since it's a re-paint, who knows what it could be.

[Donald H.]

Re: Gelcoat Removal

My hood was repainted about 5 years ago with gel coat then BC/CC. I having the whole car repainted, including the hood. I can tell you that nothing touches the gel coat. I've tried Captain Lee's Spra and Strip. The only thing that will touch it is sanding.

Don

[Jim S.]

Re: Gelcoat Removal

Either Gel Coat or Dura Tec or ....... What ever it is , if paint remover won't get it, then sanding is your only option for removal .

Brings up the question though , why remove it ?

Jim

[Russ S.]

Re: Gelcoat Removal

Plastic media blasting may remove it. I've never tried it tho.

[Tom A.]

Re: Gelcoat Removal

You don't want to remove the grey. It is a gel coat of sorts. The fiberglass was sprayed into a mold with a chopper gun the moved to a press (i.e. press molded). Before pressing the outer surface was covered with resin by pouring by hand from coffee cans. The was a specification of how many cans per part. After being uniformly spread the press was closed until the material cured then removed from the mold. This procedure is described in Noland Adams book on mid-years. If you remove paint and primer carefully you will be left with a uniform covering of grey resin. Though not technically gel coat it serves the same purpose. The surface before resin was extremely porous. You will notice when stripping paint inside the engine compartment it does not have the resin coat and stripper will quickly break down the fibers.

[Donald H.]

Re: Gelcoat Removal

Tom, great information. I've been stripping my 66, and wondered why the fibers tend to come loose on things like the inner fenders and other under hood locations.

Don

[Chris S.]

Re: Gelcoat Removal

Question - how thick is the dark gray "primer"

[Tom A.]

Re: Gelcoat Removal

It would be almost impossible to determine the mil-thickness of the resin (not primer) coating as it migrated into the chopped fiberglass surface and became an integral part of the surface. If you sand until it is no longer evident you have opened up the coarse fibers and created a very porous surface. Gel coating is the most effective way of restoring the non-porous surface (my experience) others will argue the merits of other methods but they may not give the same long term stability (my experience). I've tried them all over the last 40 years and this is what works best for me.

[Rod K.]

Re: Gelcoat Removal

Tom,

When did this process start? Would something similar (not grey) have been done during the C1 era (post '53-'54 startup)? What process produced the "resin-rich" surface of C1 panels?

[Tom A.]

Re: Gelcoat Removal

I would guess the same process but that's a guess not fact. I will research and see if I can find info.