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Re: ply thickness - glass weight tradeoff
By:Al Gunther
Date: 3/31/2001, 10:55 am
In Response To: ply thickness - glass weight tradeoff (Chris Luneski)

A lot depends on two factors, what kind of beaches and surf you will be landing on and what you feel about maintenance. My first boat was 6 mm plywood with epoxied and ring nailed clamps, no glass. I used it on a rocky beach and often landed in 2 foot surf. After each season, the bottom required some work and repainting, but it held up fine. My second boat was 1/4" cedar strip with 4 oz glass and after two repairs, which involved reglassing and revarnishing during the first season, I found myself jumping out to pick it up before hitting the beach. I much prefered the plywood for it's durability, although it was too heavy for use as a dinghy. I found the plywood flexed more than the glassed cedar.

For a small S&G, I'd use 4mm, and no glass except on the seams.

Al Gunther

: I will be building a double paddle canoe of my own design in the near
: future, and I would like it to be as light as possible consistent with
: reasonable strength. This version will be sort of stitch & glue but
: built over station molds. It is a shallow V with eight panels (four per
: side) and the angles should help stiffen the boat. Four mm ply and 4 oz.
: glass would produce a light boat, but I am not sure I am comfortable with
: that combination. Now the question: what is the weight-strength tradeoff
: between using 4mm ply and 6 oz. cloth vs. 6mm ply and 4 oz. cloth? Are
: there other combinations that would be better, i.e., extra layer of glass
: on hull bottom?

: Thanks for your help.

: Chris Luneski

Messages In This Thread

ply thickness - glass weight tradeoff
Chris Luneski -- 3/30/2001, 2:28 am
Re: ply thickness - glass weight tradeoff
Al Gunther -- 3/31/2001, 10:55 am
Re: ply thickness - glass weight tradeoff
Geo. Cushing -- 3/30/2001, 5:21 pm
Re: flex is good
Dean Trexel -- 3/30/2001, 9:37 am
Re: flex is good
Lee Gardner -- 3/30/2001, 2:35 pm
Re: flex is good
Chris Luneski -- 4/8/2001, 2:05 am