I use Titebond III on tight joints that I can clamp or use screws & GelMagic epoxy where there is any non perfect fits or voids. I use fasteners when I can, usually not on spars. So far I haven't had a joint fail but then, I never boiled a boat.
From: John Kohnen <jhkohnen@...
Sent: Saturday, March 23, 2013 11:30 PM
Subject: Re: [Michalak] Re: TBIII
Titebond III may not be "waterproof," but the "water resistant" tests it
passes are pretty rigorous. Titebond III is a "Type I" glue and Titebond
II is a "Type II" glue. The below is from Titebond literature:
"What is the difference between the ANSI/HPVA Type I and Type II
"Both of these tests are conducted using 6” by 6” birch laminates glued
together to make three-ply plywood. The test for Type I is clearly more
stringent than Type II, and involves boiling the glue bonds and testing the
specimens while they are wet.
"Type I testing involves cutting the 6" by 6" assemblies into 1" by 3"
specimens, boiling them for 4 hours, then baking the specimens in a 145°F
oven for 20 hours. They are boiled for an additional 4 hours, then
immediately cooled using running water. The specimens are sheared while
wet, and the bonds must pass certain strength and wood failure
requirements to pass the Type I specification.
"Type II testing involves cutting the 6" by 6" assemblies into 2" by 5"
specimens, soaking them for 4 hours, then baking the specimens in a
120°F oven for 19 hours. This is repeated for a total of three cycles, and
bonds must not delaminate to pass the Type II specification."
On Sat, 23 Mar 2013 21:53:03 -0700, john c wrote:
> i think the issue with pva glues, whether 1,2,or 3 is that they are
> water based and soluable if soaked for long periods.I guiess the label
> 1,2,and three just indicates how much more water resistant it is.Sure
> build your boat out of solluable glue.It will be fine untill it gets wet
> for too long.Until then? its fine.
The louder he talks of honour, the faster we count our spoons. (Ralph
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