Gel coat repair

I’ve been using Prestec for gel coat touch up because that’s what other A&P’s have recommended. I’ve been watching gel coat repair videos on YouTube. Mostly boat because that’s what’s on there. Has anyone tried boat gel coat on gliders? I am not cheap but if I can use a more readily available product at a lower cost. I am all for it.

I've successfully used Evercoat laminating gel coat from West Marine to repair both original factory surfaces and Prestec surfaces. I started with it because there was a store nearby and the Prestec shelf life is not so great. For deep gouges and nicks I fill with a mixture of that and cotton flocking. Like everything, the problem is getting the color match right. Who knew that there were so many shades of white?
ROY

Who knew that there were so many shades of white?
ROY

There are at least twenty-four different shades of white. I looked in my sock drawer.

On Sunday, November 29, 2020 at 1:10:53 AM UTC-8, Roy B. wrote:
I've successfully used Evercoat laminating gel coat from West Marine to repair both original factory surfaces and Prestec surfaces. I started with it because there was a store nearby and the Prestec shelf life is not so great. For deep gouges and nicks I fill with a mixture of that and cotton flocking. Like everything, the problem is getting the color match right. Who knew that there were so many shades of white?
ROY
That’s good info! My glider is s bit of a Frankenstein because of previous damage history. Multiple shades of white. As long as it flys well I don’t care. I know what you mean about the Prestec shelf life. I stuck mine in the fridge hoping it’ll extend the shelf life.

No problem with the Evercoat? What are using to cure it PVA?

I’ve been using resin and Cab-o-sil for deep gouges. I have an old Bayliner Trophy I’ve been practicing gel coat repair on.

Charlie

Charlie:
The Evercoat comes with its own hardener which I think is PVA based (whatever it is, it smells awful). When I wanted to thin it for spraying I used regular acetone which is also good for cleanup. I found it helpful to lightly sand a larger area than I was going to repair, then mask off the repair area as a smaller section (of what was sanded) that I would use the new gelcoat on. So you went from old gelcoat, to the sanded area, to the newly sprayed area. This allowed the colors to blend a little better than just spraying new gelcoat on the old gelcoat.
ROY

On Sunday, November 29, 2020 at 10:35:58 AM UTC-8, Roy B. wrote:
Charlie:
The Evercoat comes with its own hardener which I think is PVA based (whatever it is, it smells awful). When I wanted to thin it for spraying I used regular acetone which is also good for cleanup. I found it helpful to lightly sand a larger area than I was going to repair, then mask off the repair area as a smaller section (of what was sanded) that I would use the new gelcoat on. So you went from old gelcoat, to the sanded area, to the newly sprayed area. This allowed the colors to blend a little better than just spraying new gelcoat on the old gelcoat.
ROY
MEKP (methyl ethyl ketone peroxide) is a typical catalyst for polyester resins. Some gelcoats won't harden up on the surface if they're exposed to air.. For finish gelcoats, manufacturers typically put a surfacing compound that rises to the surface and seals the polyester from air. Laminating gelcoats don't have the waxy surfacing compound because they will have additional layers of structural material bonded to them. Those can be made to cure by sealing them with PVA (poly vinyl alcohol). PVA is water based and can rinses off with water or is shed during wet sanding.

MEKP is particularly nasty if it comes in contact with mucus membranes (such as eyes). Take appropriate safety precautions when using it.

Hope everyone has a fruitful repair / refinish season.

Craig
JN