Making a Laminated Bent-Shaft Paddle
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Fiberglassing the Blade
Arrange the cloth: Secure the paddle so that the
blade is horizontal. Some epoxy workers advocate
applying an epoxy coat on the wood before
fiberglassing; others apply the first epoxy coat to the
glass. Choose the method your prefer.
Cut the cloth generously over-size; leave between
1-2" of overhang on all sides.
The reason becomes apparent after you apply the
first coat. With adequate overhang, the excess resin
will run down the glass; with inadequate overhang,
the resin will collect on the underside of the blade.
This creates unpleasantries as you remove these
drips.
Apply the epoxy: Pour a generous amount of epoxy
on the blade and spread evenly over the surface
with a squeegy, removing excess epoxy. The cloth
tends to shift, so work carefully and squeegy to the
edge.
After the epoxy has dried, trim off the excess cloth,
turn the paddle over and glass the other side. The
second and third coats of epoxy can be applied to
each side without allowing the epoxy to cure.
I position the paddle vertical for drying on these
coats.
I used a spar varnish on my first paddles, and oil on a latter one. With use, the oil-finished blade did not prevent water absorption,
and subsequently the wood laminates swelled. This did not result in any cracks or failure, but it created some concern. The
varnished blades were scratched and also allowed water to get to the wood.
I wanted a more durable blade and also wanted some protection for the epoxy tip/paddle joint. Fiberglassing both surfaces of the
blade added between 2-3 oz to the final paddle weight, and in my opinion the durability offsets the weight increase.
The only fabric I have used on blades is Raka 3.2 oz and West epoxy system 105/207. The cloth has a very closed weave, but I
found it very easy to use (unlike the Raka 5oz cloth I used for my canoe). You can purchase lighter weight cloth, but it seems
logical that the strength would also drop off. Perhaps someone has studied the best compromise for weight vs. strength in
paddlemaking. Let me know if you have.
Here is the process I used: