Kerfing for difficult gunwale bends?

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LesForgue
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Kerfing for difficult gunwale bends?

Post by LesForgue »

As noted in Matt's instructions, The Trapper canoe has what could be a difficult bend at the ends of the gunwales.
I had an uncle who used to kerf boards and sticks to bend them.
Would kerfing be okay on a major structural piece such a gunwales?
Or would it weaken it too much?
I'm thinking epoxy saturation would restore any strength/integrity lost to kerfing - Please correct me if I'm wrong about that.
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Les Richard Forgue
OnkaBob
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Re: Kerfing for difficult gunwale bends?

Post by OnkaBob »

Not sure but I suspect that with the direction of the stresses involved it would be OK.

I would laminate 2 thinner pieces but that's just personal preference.
Cheers, Bob

Laker 13 - christened and slimed (just).
Laker accessories underway.
LesForgue
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Re: Kerfing for difficult gunwale bends?

Post by LesForgue »

Thanks Bob,
I will try to force the bends without kerfing and only try kerfing as a last resort.
I have no table or band saw,; but with proper jigging probably I could make thin strips for lamination with my hand held circular saw; there at least 2 maybe 3 Trapper builds journaled on this forum so I know some have successfully bent the gunnels all the way to the end of the bow.
One factor is that it is hard to find long pieces truly clear of knots and at a knot they will likely break rather than bend no matter how thin the strip is - kerfing might make a piece with knots work okay.

and Matt gives the tip of bending the gunnel far as it will go and leaving it like that for some days, then bending it more and again leaving it a while, then maybe it's ready to do the complete bend. "Training" the wood strip over time.
Les Richard Forgue
tx river rat
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Re: Kerfing for difficult gunwale bends?

Post by tx river rat »

Borrow your wife's hair dryer , and heat the wood as you bend them, I have done this with stubborn pieces before.
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Re: Kerfing for difficult gunwale bends?

Post by jem »

Kerfing would be fine so long as you fill in the gaps.

Hair drier or heat gun will help the wood bend. Careful not to scorch it.
-Matt. Designer.
Mick
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Re: Kerfing for difficult gunwale bends?

Post by Mick »

G'day Les,

Have you thought about steam bending your timber?

http://www.thomasnet.com/articles/proce ... steam-wood
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