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P Doug (WA)

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I'd like to play around some with making a mast using bird's-mouth jointery. I have been looking a router bits and wondering which is best. Make 6, 8 or 16 sided. Or, forget the bit and try to cut the joints on a table saw. I also like Charlie's idea of making the paddle for the Birder using the bird's-mouth jointery.

Got any input on this SLOOOOOOOOOOOW forum?

Where is everybody, busy putting boats away for winter?

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I used just a table saw and some featherboards. The router created too much tear out in the fir I used. I would expect that spruce would react the same way. There was some tear out on the table saw as well, but not as much. I used and recommend thickend epoxy to glue it up. I used hose clamps, others have used bicycle tubes, duct tape, rubber bands, anything that will hold it together firmly. I am thoroughly impressed with the mast, and plan on using bird's mouth spars on my next two boats.

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I would probably not use polar (yellow or tulip). Stika spruce seems to be the wood of choice for professionals and old salts, but the Sitka spruce supply in the desert leaves something lacking. :D The strength is in the grain of the wood, making it naturally sheer resistant. The stronger the graon, the better the sheer resistance. Hickory, ash, and oak also have great sheer rsistant properties, but are also quite heavy, let alone open-grained. I chose Douglas Fir because of its similarity in properties to Sitka Spruce. Make sure your wood is milled the right direction (quarter-sawn) in the final product.

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ALL of the spars I've built birds mouth style ( 8 so far) have been Doug fir. It's pretty widely available, fairly cost effective and can be picked over for the lighter boards. If you choose carefully the spar won't be much heavier than spruce, and you can always slightly reduce the size for the higher strength of fir.

Try to select grain that looks as close to this as you can. This is the worse of the two boards I recently bought- 30 bucks each- 18 feet long 1 x 8s


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Although it was NOT a part of the plans, I built a birdsmouth mast for the Spindrift, just to see what would happen. Never done one before.

I used Doug Fir. Starting with some not so pretty boards, which I ripped up to get some of the better stuff off the sides. Clear, tight grain works best. More on that later.

I used a router bit, designed for making birdsmouth joints. This one was 12 sided, which made the final mast almost round, with very little planing needed. Table saw would be fine, but I don't have one.

For clamps, I used the same cheap tie wire I used to stitch the boat together. Twist it and it will clamp the snocker out of it. About every foot. Once you get the bottom started (held together with rubber bands) after about 5 feet or so, the staves just slide together.

To taper the mast, I planed them AFTER I cut the joints. Would do that in reverse next time, as some of the staves wanted to roll as they were being planed down. Left some of the joints a bit loose. Not a problem with epoxy, but not as neat as I would like them to look.

For some reason, 2 photos is all I'm able to attach per post, so I'll do a series of them. For some reason, I have to log on to see the photos.



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FWIW, last winter I made a new gaff for my Weekender using the birdsmouth method. It was probably more work than needed for a small spar like that but it was a good experience and the stick served perfectly over the summer.

I used some clear pine trim from Menard's. It was about 3/4" thick and maybe 3" wide. Cost more than buying something larger but I only needed a few pieces and there was almost no waste. I planed the stock to the desired thickness and ripped to width. I used a regular V-groove bit in the table-mounted router and that worked just fine.

I made plugs for the ends and epoxied everything up using zip ties to clamp the staves together.

Sorry no photos of the process but here's one of the finished gaff. It's in the middle. the old one which may have been burnt in Kydocfrog's fireplace by now is on the left.


And for fun here is a closer shot of the jaws.


The only metal used on the gaff are a couple of pieces of brass rod driven through the jaws and spar and peened over.

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This is more info than I expected. Now I am excited to have a go at it. I head to Portland, Ore, next week end to visit my daughter. There are a couple good wood stores there! Maybe pick up some good DF and the Okume for the Birder at the same time (see what mood the wife is in :lol: ).

Thaks for all the pictures and info. Nice to see the forum pick up a little too.

Comment off topic - Anyone read Lonsome Dove or watch the movie? I read the book twice and just finished watching the movie for the 5th time. I have to watch it about every other year. Great!

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I put birdsmouth spars on my weekender too. I used a tablesaw with a dado blade set at a 45degree angle.

Some hints:

1. cut the staves from a 2 x 10 or wider - the staves will have straighter grain than if you cut the staves from a 1 x 10 or longer.

2. If you us a 2 x 10 be ready to complete the spar within a day or two - even on kiln dried lumber the center of a 2 x 10 has enough moisture to cause some crazy twisted staves.

3. before you assemble your spar, roll up a magazine or newspaper to the same diameter as the center bore of the spar and use this as a "core" to build your spar around. You only need a 1-2 foot core to help form the spar, the remaining lenght just "snaps" into place. Be sure the wrap the paper core with clear packing tape to prevent the epoxy from sticking to it.

4. The Woodenboat article didn't recomend any particular type of wood for these type of spars. Just make sure that if there are any knots in the timber that they are "tight" knots. 2x10's usually come from larger trees and have fewer and tighter knots. I used white pine for my spars and there were knots ( my staves were 3/4 inch thick)

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On the 22 foot stick I built for a gaffer over in Florida, I needed to add blocking in specific places for where the shrouds landed, plus several other spots. So I protected two opposing mouths from epoxy, glued and clamped as usual, then popped the two halves apart. Fitted the blocking, etc and then glued those two mouths. Worked out quite well


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