Gelcoat restoration. Advice, please.

johnalison

Well-known member
Joined
14 Feb 2007
Messages
39,832
Location
Essex
Visit site
You have to follow up oxalic acid with wax. But I’m sure you’re right on bad staining, only compounding removes it for good. Followed by wax or it will be back, if not in a fortnight, then in a few months.
I gathered from a friend that in time the wax needs to be stripped off before rewaxing to prevent early recurrence of the stain. He used cellulose thinner, and his boat certainly looked good, but for how long I don't know. Staining varies a lot from place to place. We stained badly every time we went through the Netherlands, but for the last few years in home waters I haven't had to treat the hull at all, other than simple cleaning and waxing.
 

Tiger Moth

New member
Joined
12 Jun 2023
Messages
24
Visit site
Thank you all, your advice is greatly appreciated. What I didn't say was that the boat, on its trailer cost me £400.

I was hoping that I could restore the gelcoat but with so many options I could spend a long time finding the right one. The prospect of so much rubbing and sander wielding makes my eyes widen and the mild arthritis in my shoulders is also sending me messages.

Correspondent johnalison gets the banana down the chute for telling me that "In the last resort you can end up painting the hull, which will be necessary sooner or later anyway." That settles it, those two cans of Toplac that I bought 5 years ago are coming out. I'll do my best, with a new brush, to make it look good and smooth. When finished I'll post a picture.

Again, thank you for your contributions.
 

Humblebee

Well-known member
Joined
10 Nov 2001
Messages
1,713
Location
Muchalls
Visit site
Thank you all, your advice is greatly appreciated. What I didn't say was that the boat, on its trailer cost me £400.

I was hoping that I could restore the gelcoat but with so many options I could spend a long time finding the right one. The prospect of so much rubbing and sander wielding makes my eyes widen and the mild arthritis in my shoulders is also sending me messages.

Correspondent johnalison gets the banana down the chute for telling me that "In the last resort you can end up painting the hull, which will be necessary sooner or later anyway." That settles it, those two cans of Toplac that I bought 5 years ago are coming out. I'll do my best, with a new brush, to make it look good and smooth. When finished I'll post a picture.

Again, thank you for your contributions.
Lots of good advice above, I would just add that with care you should be able to paint your boat without leaving brush marks. Maybe two thin coats of undercoat then two of top coat (sounds like you've got plenty). Applied with a roller then very lightly gone over immediately with just the tips of a soft brush should do the trick. Technique is called "tipping off", bound to be videos on the internet somewhere.
Look forward to seeing the pics!
 

Tranona

Well-known member
Joined
10 Nov 2007
Messages
41,482
Visit site
Thank you all, your advice is greatly appreciated. What I didn't say was that the boat, on its trailer cost me £400.

I was hoping that I could restore the gelcoat but with so many options I could spend a long time finding the right one. The prospect of so much rubbing and sander wielding makes my eyes widen and the mild arthritis in my shoulders is also sending me messages.

Correspondent johnalison gets the banana down the chute for telling me that "In the last resort you can end up painting the hull, which will be necessary sooner or later anyway." That settles it, those two cans of Toplac that I bought 5 years ago are coming out. I'll do my best, with a new brush, to make it look good and smooth. When finished I'll post a picture.

Again, thank you for your contributions.
To get a decent finish with Toplac the preparation work is almost as onerous as polishing the gel coat. Refinishing large areas such as hulls is 80% preparation.
 

Tiger Moth

New member
Joined
12 Jun 2023
Messages
24
Visit site
To get a decent finish with Toplac the preparation work is almost as onerous as polishing the gel coat. Refinishing large areas such as hulls is 80% preparation.
That's understood, thank you. Fortunately Toplac professes to need neither primer nor undercoat when painting sanded and degreased GRP. Also fortunate that GRP and paint are much the same colour. I may even get away with one coat but I doubt it.
 

lustyd

Well-known member
Joined
27 Jul 2010
Messages
11,621
Visit site
If you have an old UV damaged gelcoat surface where fine dust comes off when you rub your fingers over it the surface
In my experience, more often than not that’s a build up of old uv damaged wax and a wipe with alcohol removes it easily. The problem is often that people don’t think to clean before they try to wax, polish or paint.
 
Top