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Re: Another vote for Precoat
By:Tim Stough
Date: 3/31/2000, 1:42 pm
In Response To: Precoat or not?- A survey (Larry C.)

> What is the LATEST on this hot topic. I'm almost ready to start glassing
> my Expedition. Do I precoat the wood or wetout glass over bare wood. There
> seems to be good arguments for both methods. On earlier boats, I precoated
> with no problems. I find it interesting the on again, off again of this
> subject. It seems those that used to precoat, now don't and those that
> didn't, now do. Throughly confused!!

We're building a pygmy and followed the instructions to do a sealer coat. Here's a quick rationalization as to why that was exactly the way it _should_ be done. ;-)

There's no need for your precoat to be thick. I see no reason why the final result has to be heavier than the single step wetout. Also there is no reason that it must be weaker. If the wetout is done within 72 hours of the precoat, it forms a chemical bond with the precoat. I'm sure that a polymer chemist would be more precise, but I presume that a chemical bond means that polymer chains in the new coat latch onto the ends of chains in the precoat. While the number of chains between the glass layer and the precoat might be slightly less than if it were a single coat, I bet that it doesn't make much of a strength difference. (not bad for a quick rationalization, eh?)

Anyhow, it worked great on the hull of our first Pygmy and we plan to use the same technique on the deck and on our next boat.

I look forward to hearing more responses in this survey.

Later,

Tim.

Messages In This Thread

Precoat or not?- A survey
Larry C. -- 3/31/2000, 12:28 pm
Re: Precoat or not?- A survey
Nolan -- 4/3/2000, 7:30 am
Re: Precoat or not?- A survey
Steve McDonald -- 3/31/2000, 7:23 pm
Re: Precoat or not?- A survey - NOT
Larry Thompson -- 3/31/2000, 7:22 pm
Re: Precoat or not?- A survey
john -- 3/31/2000, 5:12 pm
Re: Precoat or not?- A survey
John B. -- 3/31/2000, 5:54 pm
Re: Precoat or not?- A survey
lee -- 3/31/2000, 6:02 pm
Re: Precoat "Clearification"..Please
Rehd -- 3/31/2000, 4:00 pm
Re: Precoat "Clearification"..Please
Hank -- 3/31/2000, 10:45 pm
Re: YES! . . . NO! . . . maybe?
Spidey -- 3/31/2000, 3:47 pm
Re: Precoat - Yes
Hank -- 3/31/2000, 3:42 pm
Re: Precoat? - Never again!!
John Michne -- 3/31/2000, 2:55 pm
Re: Precoat? - Yes sir
Bill Heuser -- 3/31/2000, 3:54 pm
Re: Another vote for Precoat
Tim Stough -- 3/31/2000, 1:42 pm
I vote - Precoat
Derek Schumann -- 3/31/2000, 1:18 pm
Re: Precoat or not?- A survey
Dean Trexel -- 3/31/2000, 1:14 pm