Building a hollow Mast of wood staves?

[thud]

The question came up in another forum. The poster wanted to know if four stave's were good enough for a mast less than 20'.

I think there was an article in an old WoodenBoat pub about the Mast of stave's.
I think it alluded to six or eight stave's, but NOT four.

I thought I'd pass it along to all the experts.Y:o

[Yeadon]

I've seen drawings in books that suggested you could do it. Technically, you could do it with two staves. Maybe even one if you had a really long forstner bit. Any less staves and you'll just have the hollow part.

I once did it with eight. Worked fine.

http://farm5.static.flickr.com/4036/4433960133_da0357077b_z.jpg?zz=1

And here, just for fun I once slit a mast lengthwise, then routed out the guts. I was trying to make it lighter. I succeeded.
http://farm5.static.flickr.com/4068/4532576101_18a8aa626d_z.jpg

I thought I had a photo of the stick with the guts routed out, but nope, just this one.
http://farm5.static.flickr.com/4014/4533210968_72b5663f95_z.jpg

[Nicholas Carey]

With 4 staves, it's called a box section. Ordinarily, they are rectangular, with the long dimension aligned fore-and-aft.

http://gallery.bateau2.com/albums/userpics/10004/mast.jpg

Or you can get a bit fancier: here's an approach to building one with a teardrop/foil section, from the DN iceboat association:

http://www.idniyra.org/articles/easy_mast_1.gif (http://www.idniyra.org/articles/mast_made_easy.htm)

[David G]

In those lengths eight is a more typical number of staves - either for a birds-mouth mast or a coopered mast. Six is not unheard of, and four has a long history - even for longer sticks. Herreshoff, Garden, et.al. I have a Puddle Duck Racer with a square hollow (4 stave) mast. It works just fine. The more important thing is to taper the stick to match the rig and sail size.

[thud]

Boy oh boy you guys were all over that one.
The wood work is why you guys do stuff like that. Your way beyond the perfectionist of Cabinet builders.
I liked the looks of that Tapered, streamlined mast.
I believe in the 'Shear' strength of several stave's glued together. It's also lighter than a big wood log sticking up in the air.

Years ago my nutty Hunting partner wanted me to help him build a 16' sail boat. Doing the research on that idea brought us to the mast.

I made a Dog house once, that never wore out. The Dog wouldn't go in it!:p

[Jay Greer]

Regardless of how you build your mast, if you are using sail track, I would advise you to avoid placing a glue seam on the center line of the fastenings.
Jay

[Nicholas Carey]

Boy oh boy you guys were all over that one.
The wood work is why you guys do stuff like that. Your way beyond the perfectionist of Cabinet builders.
I liked the looks of that Tapered, streamlined mast. That's for DN Ice Boat (http://www.idniyra.org). They are...interesting to sail:

http://www.idniyra.org/images/us4061.jpg

http://www.idniyra.org/images/jboots1.jpg

IIRC, 60-70 mph is not unheard of. With a light breeze of of 2-1/2 mph, a good DN will do about 10 mph off the wind and about 12 close-hauled and top out at about 14 mph on a reach.

Bigger iceboats go faster. An E-Skeeter is reported to have done a timed run on Lake Geneva (WI) at 158 mph; an old-school stern steerer, the A-rater Debutante was timed over a measured mile on Lake Winnebago (WI) at 143 mph in 1938. Here's a couple of A-raters next to a DN:

http://www.iceboat.org/wssa2/01hearst/deuce-dn.jpg

[thud]

I watched those Ice Boats on Wasilla lake in AK. They go really fast for an air powered boat. Faster than the Air!