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Re: Help with offset chart
By:Paul G. Jacobson
Date: 1/31/2000, 1:26 am
In Response To: Re: Help with offset chart (Peter)

> Hank,

> Thanks for help - it's all a bit confusing! I've figured ou a way to plot
> them on my computer so hopefully it will save some time in drawing forms
> up. I've not done this before,

If you are not used to the software, you might go faster just drawing these by hand. It will probably take 2 hours to do by hand, and 4 (or more) on the computer if this is yor first time. Does your printer take really big sheets of paper? If not, you'll be spending your time taping and gluing smaller sheets together

> . . .I'm looking at building the Auk although I
> can't fit 17feet in my garage. I'll have to shorten it to the alternative
> 14 feet if I can. This is going to be an interesting project! Peter,
> Lancs, England

How long is your garage? and what is the diagonal measure? Or, can you store the boat elsewhere?

Generally, the simplest way to shorten a design is to just place the building forms closer together when you put them on the strongback. If the design calls for spacing them 12 inches apart, and you actually space them 11 inches apart, then an 18 foot boat would lose 18 inches, a 17 foot boat would lose 17 inches, a 16 foot boat would loise 16 inches, etc. For less of a change you could reduce the spacing by less. Of course, you can stretch a boat a bit by increasing the distance between forms, too. (nice way to turn a single into a tandem!)

It seems such a shame to go from a 17 foot design to a 14 foot boat. That is quite a bit to shorten. Knocking a few inches off of either end is not a big deal -- bringing this down to 16 or even 15.5 feet. But, for more than this, you might want to look at a boat that was designed shorter in the first place. This would tend to be wider or taller in order to maintain freeboard at a given displacement.

Hope this helps.

Paul G. Jacobson

Messages In This Thread

Help with offset chart
Peter -- 1/27/2000, 5:16 pm
Re: Help with offset chart
Hank -- 1/28/2000, 12:33 pm
Re: Help with offset chart
Peter -- 1/29/2000, 12:21 pm
Re: Help with offset chart
Paul G. Jacobson -- 1/31/2000, 1:26 am
Re: Help with offset chart
Kent LeBoutillier -- 1/28/2000, 6:10 am