A Birdsmouth Mast for Skat
by Dave Burdecki (Bink)
binksboats@yahoo.com
Greetings:
Well...I heard there was some sort of end-of-season football
game yesterday...but I had real work to do. John O'Neil and I (ok,
mostly John} made a beautiful octagonal 14 foot bird's mouth mast for the
Skat. John wrote a couple of articles about the technique in
Boatbuilding and since he lives nearby I begged and whined until he agreed
to show me how its done. |
John O'Neil & the Spruce board
|
Cutting the strips
|
I bought a 16 foot 1"X12" spruce board. I needed
a mast 3 inches at the base, so the circumference was ...well, this
calculator doesn't have pi on it, so take my word that the circumference
divided by 8 plus the width of the kerfs came out to an 11 1/2 inch wide
board with about an inch leftover. |
We cut the staves on the table saw then ran them
through again to take off the rough side that would be on the inside of
the mast. This was not strictly necessary, but since that side was
going to be epoxied we went with caution. We set the blade at 45
degrees and cut a 90 degree bird's mouth along one side of the staves by
running each one through the saw twice, once forward, then flipped and run
through again. |
Strips cut
|
Cutting the taper
|
Just to be extra fancy, we cut the taper on the table
saw. The stick is straight for 9 feet then tapers for 5 feet to the
top. The taper is from 3 inches to 1 1/2 inches. We cut a 1
1/2 inch wedge from a 5 foot board and used the board as a guide on the
saw. Starting the cut at the 9 foot mark it worked like a champ! |
Now came the part that everyone dreads...epoxying the
slippery staves and assembling them into a rounded mast. What a
letdown! It was too fast and easy. I slathered while John
mixed. After 3 sides of each stave were coated we used a bottle that
was 1 1/2 inches in diameter (the inside of the mast at the bottom) and
rolled the ends of the staves around it. We fastened them together
with a large hose clamp and then used waxed twine to clamp up the rest of
the mast. |
|
A perfectly straight mast
|
He rolled the mast while I walked the spool up the
mast. The whole thing fell into shape as if by magic! Another
clamp at the top and it was all over. We had a perfectly octagonal
and straight mast. After it sets I'll start planing the ridges off
and sanding it round. I took some pics which you can see here.
The whole thing took about 5 hours with lots of breaks. Most of the
time is in setting the table saw and running test cuts.
Bink |
|