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11/01/2015

Lester Gilbert on understanding of sail making for model sail boats

Lester Gilbert wrote:
For anyone interested in sailmaking, I've just finished editing Larry Robinson's "Making Model Yacht Sails" (part 1 only) booklet and have published it as an "international" edition. I've done this, not to get rich ('cos this isn't going to happen to either me or Larry or anyone else connected with this enterprise!), but because I've spoken to a lot of sailors who want to make sails but don't know the "right" techniques, and who are being misled by incorrect accounts of how this might be done.


A sail block
(Illustration from Larry Robinson's "Making Model Yacht Sails")

From my understanding of sail making, there are two ideas I want to contradict.

The first idea is that you can make sails by accurately cutting a curve on a panel, and then attaching it (stitching, gluing) to another panel. Well, while you might be able to cut a good curve some of the time, your fingers just don't have laser accuracy in them to stick A to B and you'll hardly ever obtain reproducible or reliable results. (It might be possible to butt-join the curved edge to another curved edge with a little more reliability, but this doesn't yield what the Equipment Rules of Sailing define to be a seam. Such a sail couldn't be used in sanctioned IOM competition, though it would be OK in a development class.)

The second idea is that you can drape your panels over a "camber board" and get a nice shape that way. Well, let me be clear about what I'm knocking here. I take a "camber board" to be a length of curved surface, where the curve is like the surface of a cylinder. In this case, your panelled sail will have exactly the same shape as a single un-panelled sail and, if you wanted a three-dimensional shape, you've wasted your time (though the result certainly looks the part).

Larry's booklet is the only source I know which carefully explains the use and construction of a sail block. I am sure that this is really the only way (in your garage, please, not in some specialist workshop!) to make professional sails, to obtain reliable and reproducible three-dimensional shaping, and to be able to tweak and change your shaping as you learn about the whole business.

(Warning: Y'all should know I have ten thumbs and have never made a sail yet. What I have done carefully is to watch and talk to those who do, both professionally and as home builders, and measure the results. Making Larry's booklet available internationally is my way of telling you what I've learned.)

Bob Wells will be able to ship this within the USA, and I expect that it will also be available from Don Ginthner at GBMY. For worldwide sales, contact SAILSetc. Bob Wells' e-mail is "bob" at "islandinet.com", GBMY is "rcsailing" at "gbmy.com", and SAILSetc can be contacted through "sales" at "sailsetc.com".

I've attempted an analysis of how blocks work on a new page, Sail blocks analysis, and have a new spreadsheet there to help.

©2008 Lester Gilbert

2006-07-11

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