Builders' Forum Archives
Re: is 20 ft the diagonal
Posted by Terry Mcadams on Sep 13, 2004
Others may jump all over me for saying this, but you could probably shorten the triple if you really wanted to. I've made some fairly major design changes on boats I've built, including signifigicant shortening, widening and heightening of the sheer panels. It can be done without a degree in navel architecture, but it takes a bit of forethought on how the changes to each individual panel will affect the adjacent panels, as well as the overall trim of the boat when it's loaded.
This being said, I would think shortening a triple 8" on each end would not be all that drastic. The resulting boat will carry a bit less load, will be a bit slower and may handle a bit differently than the original design.
Assuming you're building from plans I would start with the bottom panels, at the midships station on the plans. Alter each station measurement to taper the ends gradually until you get the ends to terminate 8" less than the design. Use a pencil, as this will take some experimentation to get it right. You may have to slightly alter the end pieces that are patterned for you in the plans. You could do the same with the sheer panels, but it may be just as easy to make the panels to the original design and cut them down once they've been partially wired to the bottom panels. Bulkhead placement will probably will be the same, but you may have to move the forward deck beam and the hatches.
Now it may seem easier to just take the 16" out of the middle and not alter the ends at all. You can do this if you're crew weight is moderate and no crew member is unusually tall, but this approach will reduce the boat volume much more than retapering the ends and may make the positioning of three cockpits a bit more crowded.
Fitting the deck will be the same as with the stock design, and placement of the cockpits can be done measuring from midships.
So go ahead and try it. If it doesn't wire up well, you've only wasted a sheet or two of plywood.
Actually, I had asked CLC years ago for a design for a short, light (like 17 feet or so) double. The reponse was another 20+foot narrower tandem. Guess I'll have to get off my butt and design it myself.
And that's the long and short of it.
In Response to: Re: is 20 ft the diagonal by Jeff on Sep 13, 2004