Making sawdust

[Charlie Jones]

Ah HA- Some one else has tumbled onto splitting the spar and inserting the blocking , THEN gluing the remaining two joints ;D

Sure makes things a LOT simpler.

Well, I tried to attach  a picture, but it won't work.

[Garry]

Did you just tape a strip of plastic on the two joints to create two halves so you could work the internals and then glue up the two halves?

[Norman Colter]

Thanks for all the tips, Charlie. Garry, I used packing tape. Easy enough to run a strip down the length of two staves and stuff it into the birdsmouth. I'm going to let it sit for a couple days then split it. I'll let you know how it goes.

Norm

[SteveJW]

Norm,

For those of us that'll be building b-mouth spars soon, can you take a few pictures of the blocking when you split the staves apart?

Or Charlie, can you attempt to attach your pics again. 

Thanks Guys!!

Steve

[Charlie Jones]

I can try- I just went back and reread Frank's instructions- let's see how it works with me doing it

First, yes, I tape the opposing "mouths" so they won't get glued together, then assemble and clamp the entire spar as if it was all being glued. Make sure it's straight, or curved back so it's straight on the sail track side, which ever you need.

Here's a picture of one mast opened up , the other still in clamps.

[SteveJW]

That's great. 

Thanks Charlie!

[Garry]

Those doublers must be REALLY effective!! ;-)

[Charlie Jones]

Garry- those particular ones were at the bottom of the wooden section- they then had a tenon cut on the outside of the wooden part to fit inside the aluminum base section. The doubler extended a foot above the joint, and the tenon was a foot long.  The idea was to reinforce the area where the transition occurs.

[Garry]

That sounds great Charlie (even though I was trying to be funny about the double photo posts).

When you build a mast for a sprit boom (like Graham's designs) do you add a doubler where the boom attachment is? And at the top for the sheave?

[Charlie Jones]

Not for the sprit because that usually falls on the aluminum part. For the mast head, yes- I bore a round hole there down into the length of the spar and then either use a large dowel or turn something on the lathe, depending on what size it is. That plug is usually about 6 inches long.

I also fit doublers inside the bottom of the aluminum section. On masts that fit in holes I make them long enough to come above the partners. On those with tabernacles I make them go several inches above the pivot bolt. Then I use a compression tube through the mast in way of the pivot bolt.

Oh- and the double pictures just come out that way when you use the new attachment method to put the picture in between sections. I don't know why, it just does. Not something I did.

[Norman Colter]

G'day all,

Outside influences have kept me out of the woodshop for the past two days. (work) But this evening I've scraped together a couple minutes to push a piece of stock through a saw, and undo the clamps and split the mast. There was some leaking from a few spots on a couple joints, so I'm glad I taped the two I wanted to open. They opened right up. And the blocking fit the first try. (been working on tape measure reading)

61 days til spring.

Norm

[Norman Colter]

G'day all,

  Finally back to mast construction. Sealed the insides of the main, and glued six joints on the mizzen. Here's a couple pics.

Norm

[Joe Anderson]

Norman

Your masts are looking great. I have been entertaining the idea of making a birdsmouth mast.

I wonder what kind of wood you are using and if you had to scarf.

Also what are the dimensions or scantlings that you are using.

Are you planning on using any fiber reinforcing.

Lastly how do you think this mast will compare weight and stiffness to an aluminum mast.

Thanks.

[Norman Colter]

G'day all,

  We got more snow last night/this morning. Yuck

  But I got to work on the masts

Thanks for the kind words Joe. I'm following Grahams plans for the dimensions. I suspect they would be different for different boats. I don't have the set handy to give you exact numbers.

I'm using spruce. Started with two 24' 2x12. Construction left over from 1990. Been in my basement for the last 15 years. The specs for the main mast length is just over 23' but I just went with 24 for rough and then trimmed it later. Five of eight staves are as is, the other three have scarfes. Two from the same knot that turned end for end make the joints seven feet apart. The third one actually has three scarfes.

The mizzen is a little over 19'. It also has three staves with scarfes. I feel more comfortable scarfing a couple pieces together than using a single piece with a questionable knot.

Sealed the inside with epoxy, but no fibers. Put in solid pieces at the bottom, top, and pivot point. Plus a piece where the snotter will attach. Don't know how it compares to aluminum. I just like the notion of a wooden boat with wooden masts.

Here's some pics.

Norm

[Ken_Potts]

  I've never seen a boat made of snow before - Interesting...  ;D

  Thanks for sharing the mast build pics.  I've been following them eagerly.

[wkisting]

Norm (or Charlie or anyone else who knows...)

How do you establish the taper in a birdsmouth mast? I understand how you add the birdsmouth cut, but I don't understand how you can vary it to get progressively smaller in dimension as it tapers toward the end. Do you taper the staves BEFORE running them through the router/dado to put on the birdsmouth? I suppose that might work, but I'm still not clear about it.

I'm planning to try building masts for my CS20, so I've been following your progress with interest.

[Norman Colter]

Wes,

The taper on the masts for the Princess are from the six foot mark up. So I made my staves for that dimension first, then used a dado blade to cut the birdsmouth. Then marked the taper on each stave. At the top it's a 2 1/4 inch mast. 15/16 ths on the long side of the birdsmouth. I passed the staves through the table saw freehand. Mix in a little wood flour when epoxing together. It will fill any little variations. Graham sent me a page on the masts. I suspect he has the same thing for the cs boats as well.

Have fun.

Norm

[Charlie Jones]

I passed the staves through the table saw freehand.

I'm sorry Norm, but that line gave me chills. I've never ever recommended passing ANYTHING through a table saw free hand. I most certainly would not suggest it to a novice wood worker. I've seen a blade catch even a guided piece of wood and sling it out with astonishing force. Feeding free hand, EITHER direction is a recipe for getting hurt.

At 67 years old I am quite attached to all my fingers and want them to STAY attached.

Here's the setup I use cutting the mouths. This happens to be for a paddle, with the stave 3/8 wide and about 1/4 thick. As you can see, it's controlled BOTH directions. I always make them a bit overlong so I can trim away any snipe at the ends.

And I thought "add image to post" was working?

[Charlie Jones]

And here's what that stave looks like from the end. I used to use a dado blade also, but found it chattered too much and I wound up with bad cuts.

[Garry]

Charlie, Norm was cutting the bird's mouth into tapered staves, so I understand why he did it freehand. Your setup works well with straight staves like the paddle you mentioned. Like Norm, I often make questionable moves on the table saw without guides or guards. So far I still have all fingers although there are one or two scars that could have been much worse.

Do you have any recommendations of a guide setup that would work with long tapered staves? Can a finger guide or some variation be flexible enough for the varying width?