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Glenn Ashmore
 
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Default Resin Injection into soft wood

And I stand by what I said. I doubt that there is anyone on this newsgroup
working with timbers and anyone relying on soaking a rotten frame or
stringer with Rot Doctor is asking for trouble. The only way they will get
the same strength is to replace it, sister it or glass it after stabilizing
it.

A sound piece of clear fir has a tensile strength of about 12,600 PSI.
CPES, the most commercially available epoxy wood stabilizer, has a tensile
strength of around 4,500 PSI and, for fairly obvious reasons, there is no
ANSI standard tensile strength of rotten wood. Even Rot Doctor recommends
glass reinforcement for members subject to tension or shear.

Rot also occurs primarily at the joint with another member. On an interior
member like a frame or stringer that is usually the outboard side which is
normally subject to the greatest tension. Unless the tensile strength is
restored in one way or another the treated member will be a weak point and
risks becoming the starting point for failure.


Please pardon a short rant:
I have been participating in this news group for 7 years and in that time
have seen people espousing everything from antifreeze to aspirin to cure rot
and curtain liner to wheat flour to save a few pennies on GRP lay-ups. It
irritates me no end to hear people insisting on short cuts and off the wall
ways to save a few bucks and screw up a job.

I would guess that about half the participants in this news group are first
time boat builders/restorers looking for advice. We have succeeded in
chasing off all the pros so it is up to those of us with a little experience
to guide them. That is a responsibility that should not be taken lightly.
End rant:

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Ed Edelenbos" wrote in message
...
"DSK" wrote in message
...
"Ed Edelenbos" wrote
Hmmm.... I guess it must be different for working people. I've known
several boat yard operators and pile drivers who use this method (for
their own boats). Actually, the most common way is to use regular epoxy
resin and thin it with acetone to the right consistency. I know of a
couple rib repairs that are about 25 years old and still in place.


It depends very much on what the original structure was like (ie massive
workboat construction or slender scantling yacht type); and what stress
it's put under.


This is exactly what I said... it depends on the task. For the statement
"Unless the part is reinforced with carefully aligned glass fiber it will
not be up to the task." to be made, it assumes that either it is
unsuitable for ANY task, or that ALL tasks are the same. Neither of these
assumptions are correct.

I'll stand by what I said... it is a rediculous assertion.

Ed