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Roger Derby
 
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Not a new subject, but ...

I've had very good luck making 8:1 scarfs by supporting the two pieces atop
one another, staggered, and marked, and then planing (power and hand) for a
plane surface. Check with a straight edge. The angle is not critical, but
8:1 is thought minimal by many.

Example: to scarf two 2x4's (1.5" x 3.5"), mark back 12" (= 8 x 1.5) from
the end of each and clamp them together, staggered, with a firm support
under the lower one. If there's a "preferred surface" then flip one piece
so the surfaces will match. Remove wood until there's a smooth ramp from
the innermost mark (the one that's 24" from the end).

Flip one piece so that the two ramps are face to face, jiggle around until a
straightedge lies flat touching both surfaces, and scrawl some "witness"
marks across the join. Ensure other alignments are correct.

Protect your work surface with polyethylene.

Coat both surfaces with unthickened epoxy to fill the end grain and avoid an
epoxy-starved joint, then apply thickened epoxy (I like wood flour for
thickening). Put the two pieces together so the witness marks line up,
clamp lightly, and go away for a day or two.

It doesn't hurt to heat the pieces of wood before applying the epoxy. As
they cool, the epoxy is drawn into the wood. Otherwise the heat generated
by the curing epoxy can cause air to bubble out of the wood disturbing the
epoxy in spots. The heat makes the epoxy cure faster too.

Roger

http://derbyrm.mystarband.net/default.htm

"Bert van den Berg" wrote in message
...
I have seen wood scarfed for wood mast construction where there is a long
joint made by overlapping two pieces of tapered wood. Can anyone tell me
how you physically create the long tapered joint? I have been thinking
of
using a thicknesser with multi passes.

Regards,

Bert van den Berg