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Re: Strip thickness?
By:Garland Reese
Date: 8/10/2003, 9:47 pm
In Response To: Strip thickness? (Charlie Lesh)

: Garland: Thank you for the information. I can't wait to get my hands on the
: Chappelle drawings! I actually found a small jpeg of them on the internet
: after extensive googling, but too small to read the offset table.
: Hopefully they will arrive sooner rather than later, although the
: Smithsonian mentions it may take 4 weeks. Aaargh! Seems like they will
: solve the station problem, anyway.

: I have one question about your initial reply. You mentioned using thicker
: strips. I guess I was under the impression from Nick's book that the
: strength came (mainly) from the fiberglass sandwhich, not the wood. Am I
: way off here? I was going to use quarter-inch strips, just like I did with
: my Great Auk, with a much heavier lay up of fiberglass on the hull. Should
: I use thicker strips?

: Thanks in advance,
: Charlie

Hey Charlie,

forgive my lame engineering prowess here......yes the strength in strip composite comes from the sandwich. as the separation between inner and outer layups increase, i.e. the thickness of the wood increases, you get a siginificant increase in strength. You can use thin strips and more 'glass. Or you can increase the thickness of the strips and use a lighter 'glass layup. I think the jury is still out on which is best or which results in the greatest strength-for-the-weight-advantage The strip thickness I mentioned was what Mac had used. I think he used 3/4 on the bottom and 1/2 on the topsides. He used multiple layers of light 'glass for the layup, in and out. Extra 'glass on the stem and bottom. You might give Mac a shout. He could give you some good advice. Or you could use a layup schedule for a similar sized boat. If I wanted a bright finish, I'd use no greater than 6 oz cloth in multiple layers. Compared to the original design, I think you could overbuild the thing and still have a light and nimble sailing skiff. You will likely need a small trailer, and this boat is too burdensome to carry and drag around too much anyway, so I'd opt for durability over feather weightedness. Plus, you'll have streses from the sails, and the daggerboard (should you bump on the bottom, you can bet you will sooner or later), etc.
You might check out the Wooden Boat forum. very knowledgeable fellows over there and lots of good building advice, but not that much specifically about strip/sheathed construction. I'll drag out Mac's book. He had some suggestions for building a 'seed (layup, strip thickness, etc.). I'll let you know.......I hope that helps a little.
Garland

Messages In This Thread

Off Topic: Strip Built Melonseed.....
Charlie Lesh -- 8/9/2003, 11:04 am
Re: Off Topic: Strip Built Melonseed.....
Garland Reese -- 8/10/2003, 8:29 am
Strip thickness?
Charlie Lesh -- 8/10/2003, 12:14 pm
Re: Strip thickness?
Garland Reese -- 8/10/2003, 9:47 pm
finish
Charlie Lesh -- 8/10/2003, 11:20 pm
Re: Strip Thickness
Dick Lemke -- 8/11/2003, 1:31 pm
Re: Strip thickness?
JJ Atkinson -- 8/10/2003, 6:39 pm
Re: Strip thickness?
Rehd -- 8/10/2003, 7:56 pm
Re: Strip thickness & Lay-ups?????
John B. -- 8/10/2003, 3:39 pm
Re: Off Topic: Strip Built Melonseed.....
Garland Reese -- 8/10/2003, 8:18 am
Re: Off Topic: Strip Built Melonseed.....
Sam McFadden -- 8/9/2003, 10:33 pm
Re: Off Topic: Strip Built Melonseed.....
JJ Atkinson -- 8/9/2003, 12:43 pm