Sealing with polyester resin over penetrating epoxy?

[CRJDriver]

I made a new rear deck, fuel tank hatch cover and a rear bulk head out of marine plywood and coated it on all sides with West Marine penetrating epoxy. I had intended to encapsulate everything in polyester resin and cloth tape.

Will the poly resin bond to the wood with the penetrating epoxy? Or do I need to return the polyester and buy epoxy resin?

I know poly will not go over epoxy. Does that apply to the penetrating kind as well?

 

[jbcurt00]

Re: Sealing with polyester resin over penetrating epoxy?

Ummm, didn't this come up in your four winds thread:

you have to remove the rotten wood and replace properly. sistering it is a bad band-aid. Poly resin will not stick to epoxy. penetrating epoxy is snake oil. doesnt really work. Just my $0.02

And there seem to have been several posts in that thread suggesting that this may not have been your best course of action to safely boat this summer w/ some water damaged &/or rotten wood structure....

Maybe it isn't what you wanted to hear, but...............

 

[CRJDriver]

Re: Sealing with polyester resin over penetrating epoxy?

Ummm, didn't this come up in your four winds thread:



And there seem to have been several posts in that thread suggesting that this may not have been your best course of action to safely boat this summer w/ some water damaged &/or rotten wood structure....

Maybe it isn't what you wanted to hear, but...............

Thank you for the post. I am quite confident the boat is solid. I have spent many hours working on it with it opened up. The rot is confined to one area behind the fuel tank. I have a lot of experience working with wood, but none with resin. I would not take it out on the water if I had the slightest concerns about it failing. I do agree I will need to rebuild. I intend to keep the boat for a long time.
I had hoped to stay away from epoxy resin for cost and removal down the road. I probably should have stayed away from the penetrating epoxy and just used the poly resin.

 

[tpenfield]

Re: Sealing with polyester resin over penetrating epoxy?

Given your situation with the penetrating epoxy in the wood, you could try to rough up the wood with sand paper and then use VE resin instead of poly resin. That would be my only suggestion. I'm thinking the poly resin would not adhere to well to the epoxy and would separate upon use of the boat, etc.

 

[ondarvr]

Re: Sealing with polyester resin over penetrating epoxy?

You started with epoxy and now you are committed to it for any further resin needs in this location.

Penetrating epoxy is sort of a rip off in a couple of ways.

Thinning epoxy reduces the physical properties faster than it does the viscosity, so you end up with a weaker less water resistant product, and all they did was add a bunch of relatively low cost solvent, so you pay a higher price for a cheaper weaker product.

It doesn't penetrate much better than normal viscosity resin, so you lose there.

Preventing rot has nothing to do with penetration, it’s all about encapsulation.

 

[Bob_VT]

Re: Sealing with polyester resin over penetrating epoxy?

I was always under the impression that epoxy could go over regular resin and stick but not visa versa. As stated above you are now committed to epoxy .......... it is stronger.

 

[rickryder]

Re: Sealing with polyester resin over penetrating epoxy?

The rot is confined to one area behind the fuel tank.

I'll bet you will find much more rot when you rip the deck up this winter. Four Winns did a pretty poor job on glassing under the deck. Feel free to have a look at my thread below..... I only had a few soft spots by the ski locker :facepalm:

 

[CRJDriver]

Re: Sealing with polyester resin over penetrating epoxy?

Thank you to everyone for the advice. I should have stayed away from the penetrating epoxy and just used poly resin. I will have to rip out the sistered bulkhead, but I had intended to reuse the new rear deck I cut out of marine ply. I am committed to the epoxy like Bob stated.

This has been a lesson learned. Better to gain some experience here before doing the permenent repair!

 

[rickryder]

Re: Sealing with polyester resin over penetrating epoxy?

Like you said in your first post.....you will be doing a full gut this winter.....this is just a temp fix....come winter we can assist you in the complete resto