William R. Watt wrote:
Brian Nystrom ) writes:


Polyester resin is fine for laminating fiberglass, but it's a very poor
substitute for epoxy when you're working on wooden paddles. It's not an
adhesive and it's nowhere near as strong as epoxy.


I have polyester resin and glass fibre on the tip of my cheapest paddle
which I use in place of my lightweight paddle on "rough" outings exploring
shallow rocky creeks and so forth where it's used to push as much as to
paddle. The tip has to be sanded and touched up after an active season,
done in early spring as part of the ritual pre-season boat maintenance.
The polyester can't be built up too thick or it cracks and comes away in
chunks. However adhesion is not a problem as the paddle tip is drlled with
small holes into which the resin sinks and grabs hold.

That's all well and good, but polyester resin is lousy if you're simply
trying to apply fiberglass over wood, as you would with epoxy.

I'd use whatever resin I had on hand, and if both, then the least cost.

Well, I guess that's one difference between us. I'll use whatever
product is best for the application, rather than trying to save a few
cents, which is quite literally the difference when dealing with the
small quantities used on a paddle tip.

As for cooking oil, in spite of theoretical musings, it has worked well
for me and is cheap. Like boot grease I rub in until it's warm. That is
supposed to help it sink in.

There are a lot of myths surrounding wood finishes in general and oil
finishes in particular. Bob Flexner's book "Understanding Wood
Finishing" contains detailed explanations of all types of finishes and
debunks the common myths and misconceptions about them. Rubbing oil
finishes is a good example. It actually REDUCES penetration, as the heat
causes the oil to cure more quickly, so it has less time to penetrate
before it becomes too thick to do so. Rubbing oil does more for the
tactile sense of the woodworker than it does for the wood.