Too early to be concerned about the mast?

[mrthethird]

I have planned on making a round, hollow mast for this weekender. I am getting to the point in construction where some fore-planning may be needed. As you may know, the plans call for a solid, square mast. As I bring my boat to 3D, I will need to create the mast-box, and therein is the problem. Will my round mast fitting into a square mast-box prove to be an insurmountable problem?

I envisioned making a round mast-step at the bottom, and cutting a round hole in the deck, making a round collar to keep the water out. Is this enough support for the mast, or am I asking for trouble here?

Has anyone else tried this? I would appreciate any advice or comment.

[Frank Hagan]

I have a round mast. I made the bottom portion a little larger in diameter, and then put a flat on one side. Jammed it into the mast box and used a traditional technique using "mast partners" ... you jam wedge shaped shims into the space around the mast.

Sealing it off was accomplished with the scraps of styrofoam you see in the picture and an ace bandage, then painted with liquid "whipping compound" from the chandlery:

Latex paint works as well, as long as you let it dry well between coats.

My page on making a bird's mouth hollow mast is at http://users2.ev1.net/~fshagan/mastm.htm, including my initial failure ... that first mast ended up being re-used for a couple of other projects. I liked the final result of the one that survived!

Its a good method to use, but Charlie Jones here has a very good recommendation to glue up two halves ... by not putting glue on two of the staves 180

[Barry Pyeatt]

One other solution is to have a square tabernacle and above the hinge point transition to the round mast. I've seen a couple done this way now and they look very salty. The portion above the tabernacle hinge is solid, transitions to round then a shoulder cut and then cut down to a hex to fit inside the birdsmouth mast. Both of the birds mouth masts in this case were even dimensions until the last couple feet at the top where they tapered to a hex transitioning thru a shoulder to a round plug.

[Dave R1]

I did as Barry suggests. I used a piece of cedar 4x4 for the tabernacle. The mast is an old round one that was given to me. I took off the corners of the 4x4 near the hinge point so there's a nice transition from square to round.

[Greg Luckett]

On Dragon we made a wooden collar to reinforce the decking plywood. It is cut in a 6 inch diameter on the outside then a hole was cut to allow the round mast to be placed. Ben painted it with some of the red paint he used on the hull, which contrast nicely with the white deck. You could do something similar to make an adapter for the square deck hole.

Incidently, in The Sharpie Book, by Parker, it shows using leather to cushion the mast where it goes through its thwart. If we make a better mast for Dragon this winter we will also do this. The current one is made of PVC pipe filled with hammered in pressure treated and shaped 2x2. It is heavy and still bends too much. A nice, solid ash mast would be nice. We have some logs sitting behind the house that should work nicely.