Gelcoat Repairs Around Windows

[Benobo]

Hello all --

Two years ago I purchased my first boat (a Windward 28) and have been slowly working away on it whenever I can. This spring I decided to pull off the windows (8 - 4' plexiglass panels, 4 on each side) and have new ones made.

The new windows are being fabricated as we speak, but when pulling off the old ones I found that quite a bit of the gelcoat was coming off with the Sikaflex, in some cases as far down as the fiberglass. I did my best to keep it to a minimum, but in many places it couldn't be avoided.

I'm about to start prepping the cabin top for the new windows and was wondering what you would recommend as far as repairing those places where the gelcoat came off. Should I just leave it, and rely upon the new layer of Sikaflex that I'll be applying to fill the voids, or should I go to the trouble of repairing those patches where I'm down to the fibreglass (and if so, how)?

Any help you can give would be hugely appreciated! I'm new(ish) to the forum (I guess I've been a voyeur for a while so...hello!

Ben

[scottyt]

you could use the sika to fill the voids, but you really should "seal" the glass.

[Benobo]

Originally Posted by scottyt

you could use the sika to fill the voids, but you really should "seal" the glass.

Thanks for your reply, Scott. How would you recommend I do this? I've read on other posts about gelcoat repair kits -- would that be the way to go?

[bluwateronly]

I would use a mixture of thickend apoxy around the edges and sand to fit. Add some white pigment into the epoxy and should be fine and not show to much.

[Benobo]

Originally Posted by bluwateronly

I would use a mixture of thickend apoxy around the edges and sand to fit. Add some white pigment into the epoxy and should be fine and not show to much.

Anywhere the gelcoat came off will be hidden by the new windows, so I'm not at all concerned about appearances. I'd only do it if NOT doing it would be to jeapordize the structural integrity of the fibreglass.

I just came back from the local chandlery and he's saying not to bother filling in the holes -- just to rely on the Sikaflex to do the work. Anyone else want to weigh in?

[mitiempo]

I would mix epoxy and thicken it to fill the voids as bluwater said. The Sika is a sealant but is not really designed to be a gap filler. A bit of pigment can be used but if it will be covered by the Sika I wouldn't bother.

[Benobo]

Originally Posted by mitiempo

I would mix epoxy and thicken it to fill the voids as bluwater said. The Sika is a sealant but is not really designed to be a gap filler. A bit of pigment can be used but if it will be covered by the Sika I wouldn't bother.

Thanks Brian. Is there a particular product and thickening agent you'd recommend?

Looks like we live in the same town...I should try and convince you to come and help me with it

[mitiempo]

I'd use colloidal silica. You can buy the West product or if you go to Industrial Plastics on Cloverdale (between Douglas and Blanshard) they have it for less prepackaged in plastic bags. You want it to be peanut butter consistency, thick enough to stay but still moist. Where is your boat?

[Benobo]

Originally Posted by mitiempo

I'd use colloidal silica. You can buy the West product or if you go to Industrial Plastics on Cloverdale (between Douglas and Blanshard) they have it for less prepackaged in plastic bags. You want it to be peanut butter consistency, thick enough to stay but still moist. Where is your boat?

I keep it up in Tsehum harbour, near Van Isle Marina. I race with SNSYC in the summer but it's on someone else's boat. Are you down in the inner harbour, or out on the peninsula?

As an alternative to colloidal silica, could I potentially use that putty-style epoxy? Just thinking it may be easier to apply and sand down once sealed...

Thanks for all your help!

[mitiempo]

Yes, there is a premix epoxy from West that would be easy to use. It's called Six-10.
I keep my boat in the harbour near Fisherman's Wharf.