Ah yes: that explains it.
I was interested in the fishmouth approach - I hadn't run across
this method before.
I started by asking myself: Why wouldn't I saw on a 22.5 degree
angle? This would be economical in the spar material: only the kerf
would be lost. But visualizing the clamp up, it would be a nightmare,
I'm su the fishtail approach is largely self aligning I'd think.
And your approach ought to be very warp resistant.
I recall that the 2 part sandwich approach that I used allowed a
little bowing to show up after a year or two.

I also recall that a hollow shaft loses 5% of its strength (in torque)
while losing 25% of its weight, for a 50% of radius, hole.

Brian Whatcott Altus OK

On Sun, 15 Aug 2004 06:54:41 -0400, Jonathan
wrote:

No, it uses 8. I used 1x4 fir decking and got 3 strips per board, and I
inadvertently used all nine instead of discarding one

In the process of clearing a space to lay out the mast for gluing,
checking all of the 45 degree cuts for full cut through (my saw depth
changed without my input after the first 4 cuts, and two strips had to
be cleaned up with a Sandvick scraper)

I forgot to discard one of the lengths I was wondering why the hose
clamps I used to glue it up were suddenly too short when they had plenty
of room on my test, a 2 foot spar.....

*Fortunately*?, my epoxy mix was thick enough to fill most of the gaps.
There are a few places I will use the West syringes to fill some
hairline spaces.

I was wondering if anyone would catch that goof

Jonathan



Brian Whatcott wrote:
On Sat, 14 Aug 2004 22:16:33 -0400, Jonathan
wrote:


Took a detour to work on Ocean Planet for two weeks and to make a mast.
Interior is painted. Almost there !

http://home.comcast.net/~jonsailr



Nicely illustrated! But the mast uses 9 45 degree segments?
you have a gap or two, I reckon.

Brian Whatcott