Fiberglass dinghy repair

[Big E]

Looking for advice on patching a hole along the spine of an old, ugly fiberglass dinghy... Never having done fiberglass repair, I think this project will be good practice...any suggestions would be appreciated.

[Bill Goldsmith]

I would suggest downloading the West System manual on fiberglass boat repair, and then decide how to proceed.

http://www.westsystem.com/ss/assets/How ... enance.pdf

[GeorgeH]

Dinghy repair is pretty easy. I have to patch mine every season because of the rocks on the shore of Setauket Harbor. Its basically resin, setting agent and fiberglass cloth and some sanding. My dinghy has a small keel that punctures and I have to fill the hole with styrofoam then glass over it and sand it to the natural line.

I clean the bottom and sides of the dinghy, sand down all of the holes and cracks that I plan to glass, pre-cut the fiberglass cloth to fit over the holes I am repairing and then mix the resin with agent and put in on with a small paint brush, add the fiberglass cloth, a little more resin and wait for them to dry before sanding. On the bigger holes you will have to build up the layers of cloth and resin. The more you do it the more confident you get about working with fiberglass and resin.

Good luck.

[Oswego John]

If you mix larger amounts of epoxy or polyester, after it is mixed, store it in a pan or something with a wide area. If you keep it in a tin can or plastic cup, the mix will kick too soon before you have a chance to use it all up.

Also, there are several types of catalysts (part B) available from fast setting, medium and slow setting.

Good luck,
O J

[Steve Laume]

Has anyone tried using Kevlar cloth or mat to repair the drag areas on your dinghy? This is very common practice on white water canoes. They tend to wear at the stems the same way dinghies wear away their keels.

I know some people add a brass half round but this seems to fail on several counts. First you need to drill holes to screw it on, brass is heavy and it doesn't slide along rocks very well. Kevlar is light and can be epoxied on. I have also heard of using some graphite in the resin to make it slide better but do not know how this would effect bottom paint.

I am pretty careful about dragging Feather but she is heavy and we visit a lot of rocky beaches. I have repaired the keel a couple of times now and the next time I have to do it, I will try using Kevlar.

I use the West system products and am very happy with the results and the ease with which they are obtained. The mini pumps are a way better idea than sliced bread, Steve.

[GeorgeH]

Kevlar matting sounds like a great idea. I glued pieces of indoor/outdoor carpeting on the bottom of my dinghy to help absorb the shock of banging against the rocks when the tide goes down.

[azucha]

+1 on West System Manual. I work with West System quite a bit. I prefer it over the cheaper fiberglass resin + hardener mix because counting the drops seems to give me an uneven working times. The West Pumps attached to the hardener and resin works everything and consistent set times. I can plan my work much better with West System. Repaired the entire cockpit sole on CD 30 with West System. I have friends that continue to prefer the resin hardener drop count method. This method has more variability than West.

[bottomscraper]

The West System manual is good. I like epoxy but I really hate the West System pumps. They are expensive, they leak and make an ugly sticky mess. System 3 Epoxy has an easy 2:1 mix ratio (I believe MAS Epoxy is also 2:1). Just pick up a few small disposable cups for measuring no mess no leaks done.

For fairing System 3 "QuickFair" is a nice easy to use product.