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Re: Fiberglass: 4oz. v 6oz.
By:Dean Trexel
Date: 4/19/2000, 7:56 pm
In Response To: Fiberglass: 4oz. v 6oz. (Scott)

: Just how much weight would I save on a 19' kayak using 4oz on the deck
: instead of 6oz, assuming I did a comparable job on each?

: Scott.

Let's assume that the ratio of wood:glass/epoxy is 50:50 (George recently posted that the ideal ratio is 33:67 and that standard building methods yeild more like 75:25.) Let's also assume your lay-up consists of one layer of 6-oz. everywhere except 4-oz. on the deck, compared to a boat with one layer of 6-oz. all around. This yeilds a ratio of 22oz per yard:24oz per yard, or 92% -- you'll save 8% of the cloth weight. Let's also assume that the ratio of cloth to epoxy is 50:50, so you'd be saving 8% of the glass/epoxy lay-up, which given the 50:50 wood:glass/epoxy ratio would mean you'd save 4% of the total weight of the basic shell of the boat. I recently weighed the completed shell of my Outer Island, which is 18' long with 6-oz all around plus an extra large patch of 6-oz on the hull, and it came to 37#. Your 19-footer should be comparable. Your savings in going from 6-oz to 4-oz on the deck would be 4% of 37#, about 1.5#.

You could lose more if you took a leak before you paddled...;-)

Dean

Messages In This Thread

Fiberglass: 4oz. v 6oz.
Scott -- 4/19/2000, 7:07 pm
Re: Fiberglass: 4oz. v 6oz.
Hank -- 4/20/2000, 8:31 am
Re: Fiberglass: 4oz. v 6oz.
Dean Trexel -- 4/19/2000, 7:56 pm