That's the "Noble System" which was written up as "Bird's Mouth Hollow
Spars" by Aimé Ontario Fraser in Wooden Boat Magazine, July/August 1999

I've an expurgated version of the Wooden Boat article, with photos, that I
prepared if you'd like it. (Aimé spent too may words on social/dining
issues for my taste.) It's a huge file, 16 MBy, and of course it's
copyrighted material.

The scantlings given were, for an 8-sided spar:
Stave width: 0.4 x diameter of spar - taper square edge
Stave thickness: between 0.1 and 0.2 x spar diameter - (bigger for big
boats) (0.2 for spruce, 0.15 for Douglas Fir)

I think the scheme is also discussed near the back of Hassler/McCloud's
"Practical Junk Rig."

Roger

http://home.insightbb.com/~derbyrm

"Brian Whatcott" wrote in message
...
On Mon, 5 Dec 2005 16:18:40 -0600, "Art Ransom"
wrote:

I have heard that bead and cove joints can be used for mast/spar building.
Anyone ever done this?


A similar, less labor intensive method is providing strips with one
fish mouth edge - 45 degrees, 90 degrees, 45 degrees.
The fish mouth fits the inner edge of the next strip.
All held together with hose clamps or tourniquets during glueing.
There is an optimal width/thickness for a mast diameter.
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Brian Whatcott Altus OK