Gel coating on interior surfaces?

[Boatyarddog]

Originally Posted by chowdan

Curious if anyone has any experience with this?

Some of you may know i've been slowly rebuilding interior of my boat. Most of the wood i've pulled I replaced with painted wood, however part of the settee that i'm rebuilding I decided to test out a gelcoat job.

I decided that since this is an area thats covered mostly with cushions, if the gel coat cracks/looks like ****, then well I'll redo it eventually with paint regardless if i have to sand it all off.

I'm curious if anyone has applied gel coat over cabinetry? The plywood was covered in fiberglass and polyester and gel coat applied over that. Wondering if modern boats just gelcoat all their pieces before installing inside?

PS - only reason I'm doing it is because I have a ton of left over white gel coat, so figured since it's never going to get used, might as well attempt to use it.

Yes, no problem. https://www.google.com/search?q=prev...&client=safari
Use a Preval sprayer and G coat with wax, or finish g coat.
Yes, you'll have to sand after spraying, but the process isn't really that hard.
Polish with rubbing compound.
I've not experienced problems with that.
Interior temp can be controlled so it'll cure just fine.
Tinting can be tedious, but if it's white only I doubt you'll have much difficulty with burning in the transition.

[Spot]

Originally Posted by chowdan

Well i'm glad everyone is saying this a bad idea, because it's already done, so the experiment has been started regardless!

That said, the wood was saturated in thin polyester first, cured, sanded, wiped and then polyester coated with a layer of glass over it, so hopefully that will hold structure. As for flexible, well only time will tell to see how flexible this really is and how it holds up over time.

If we do get cracks in the gelcoat, well the good news is the plywood wont have delaminated and it'll be easy to remove from the boat and route out a new piece which i can saturate with epoxy and paint(which is what i typically would do). Sure does add some effort, but it's i guess an "experiment now"


I'll be doing some wet sanding over the next few evenings to see how it turns out

I like your can-do attitude Chowdan. Please post some pics during or after sanding.

[Fore and Aft]

I survey a number of boats that have flow coat liberally painted on all locker surfaces. Its a bit hit and miss as to how well it stays adhered to the plywood. Recently I surveyed a 36 year old Citation 34 yacht that had been well brush flow coated on all locker interiors. You could see that it was starting to peel of the plywood in places, but considering the age of the flow coat I would say it had worked well.
Cheers

[David B]

Originally Posted by chowdan

Curious if anyone has any experience with this?

Some of you may know i've been slowly rebuilding interior of my boat. Most of the wood i've pulled I replaced with painted wood, however part of the settee that i'm rebuilding I decided to test out a gelcoat job.

I decided that since this is an area thats covered mostly with cushions, if the gel coat cracks/looks like ****, then well I'll redo it eventually with paint regardless if i have to sand it all off.

I'm curious if anyone has applied gel coat over cabinetry? The plywood was covered in fiberglass and polyester and gel coat applied over that. Wondering if modern boats just gelcoat all their pieces before installing inside?

PS - only reason I'm doing it is because I have a ton of left over white gel coat, so figured since it's never going to get used, might as well attempt to use it.

Some fifteen years ago, I installed a small plywood shelf in the forepeak, and gave it several coats of gelcoat (because I wanted it to match the other areas in the forepeak), then sanded dead flat with finer and finer abrasive. End result is it looks like a sheet of fibreglass, and has not changed to this day.

I coated both sides and all edges, so the underlying ply is totally stable - that is probably the trick.

[Chotu]

Originally Posted by chowdan

I'm curious why this would be the worst sanding job of my life? I've grinded hundreds of sqft of fiberglass, thousands of sqft of bottom paint in my life, surely sanding down these pieces can't be that bad?

As i said before, if they fail and crack all over, i'll just pull them out, use them as templates and remake the pieces down the road. Maybe in 5 or 10 years i'll do it, but structurally they will be in better shape than the ply that was pulled from the boat, just cosmetically at that point they may look like ****.

The settee top literally had every layer delaminated and was basically unsound. To replicated the pieces I had to mark where the layers lined up to survive the journey to the shop.

You’re going to start sanding it soon, right? You’ll see....


Grinding glass = fast
Sanding paint = fast
Sanding gel coat flat/fair = pretty slow
Sanding up through the grits to get it to shine = worthy of tears

Essentially, doing this to save on paint because you have some gel coat kicking around means you don’t value your time. It’s a mind bogglingly slow way to do it and you need to use a ton of sandpaper.

I’m only trying to save you the grief. Proceed if you don’t care how long the job takes.

Remember, if you had painted it or used formica, you’d already be done right now. That’s my point.