Fiberglass over Thompson treated wood

Mudbugger

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I have an old Monark, 18' aluminum open vee, that I will be making a new transom for.

My question: if I treat the various layers of plywood first, with Thompson's waterproofing, will I be able to fiberglass them and and laminate them with glass and polyester?
 

jbcurt00

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And you'd be much better off using epoxy instead of polyester resin.

Titebond3 is a great choice to glue the ply laminations into a solid transom. Easy, cheap and waterproof once dry. IIRC, TB3 is also boil proof.....
 

Chris1956

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If you do a good job laminating the plywood and fiberglassing it, the water sealer is unnecessary.

Polyester resin is fine, IMO. Epoxy is for those repair applications that are critical, such as a crack in the hull at a high stress area. The boat was originally made with Polyester resin, and it was plenty strong.

Make sure the plywood is clean and dry, and don't spare the cloth and resin. Mix the resin with a bit less hardener to allow it to soak into the plywood for a longer time, and make sure you fill the mesh of the cloth fully..
 

jbcurt00

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...
.Polyester resin is fine, IMO. Epoxy is for those repair applications that are critical, such as a crack in the hull at a high stress area. The boat was originally made with Polyester resin,....
Take another look at his post, its an aluminum boat, not glass.

I stand behind my suggestions.
 

Mudbugger

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Thanks for all the information so far. At this time, the boat has a 1963, 40 Horse Johnson on it. If/when it fails, I doubt that the replacement would be much larger, just due the the usage and environment the boat will see.

More comments, ideas and suggestions are always welcomed.
 

fishrdan

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Thompsons has wax in it, exactly what you don't want in the wood for any epoxy/fiberglass/glue application.

If you want to "treat" the wood, Jasco Termin8 H20 will disperse into the wood and dry, then you can epoxy or fiberglass. But, you'll have to wait for all the water to evaporate out of the wood.... Epoxying the wood is the best solution, don't need to treat the wood, but you have to seal all penetrations.

On my 14' jon boat, I treated (soaked) the transom plywood with regular oil based Jasco Termin8 and nothing over the top. Been fine for 7(?) years, and if it rots, I'll replace it with the same. Transom was made out of marine plywood.
 

Scott Danforth

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use exterior grade plywood, laminate with tite-bond III, then either use linseed oil or paint with enamel, bolt in and go fishing.

with minimum maintenance it will outlast your kids
 

Mudbugger

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I have a question, not related to this topic, but related to this post.
Is there a way that I, as the Original Poster, can close this thread?
I have gotten sufficient and good information and since I don't get good notification of followup comments, should someone else comment, I would hate for them to feel that I ignored them.
Thanks.
 

jbcurt00

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You cant close a topic.... only mods and admins can..
 

GA_Boater

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You had no replies in over a month and was sinking down to Davy Jones locker. You asking to close it caused it to bob to the surface, so don't post in the thread and it will sink again.

We don't close threads unless absolutely necessary. No feelings will be hurt if you don't acknowledge.
 
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