: As a first time builder and glaee-epoxy-using-virgin, I very apprehensive
: about screwing up this phase.

: I'm looking for the specific trade offs of different cloth weights.

: Nick's book has a light weight (all 4oz cloth) and a standard layup (6oz). I
: have recieved emails from fellow BBS members suggesting a mix.
: specifically, 6oz on outside of hull and 4oz on the other 3 surfaces. I
: guess any layup would include additional layers in 'key' spots.

: My question is....All things kept the same, how much heavier would a standard
: (6oz) layup be then a lightweight (4oz). There is the obvious '2oz per
: yard' weight gain (about two and a half lbs for 20 yards), how much more
: epoxy (again, first time builder) will the heavier cloth require...any
: thoughs on its weight?

: Is 3.75 oz cloth concidered 4oz? Raka sells 3.75 not 4.

: Is 3.75 on and under the deck, with extra layers behind the cockpit
: sufficent?

Chris,

First, I think that Russ gave a nice glass schedule in response to your earlier post.

If I recall, Nick's book also presents a table of the weight difference between several glass/strip combinations. Also, Check out the test panel data that Nick and I collected. He included the lay-up weight for each data set. Or, you can estimate the weight differences by calculating the glass + epoxy weight using a glass weight fraction of 55 to 65%. I have made several measurements of the glass weight fraction in hand lay-up samples of 4 and 6 oz cloth, and this range is easily attained using the methods described in Nick’s book, here on the KBBB, and in other kayak building books.

The fill coats will require more epoxy for the heavier weight cloth but , in my opinion, not enough to worry about. As others have pointed out, you can save a lot of weight simply by being careful with the epoxy. That means try to only leave enough in the boat to wet out the glass, and minimize the size of fillets and thickened epoxy. If you are concerned about being a first-time user of epoxy and glass, buy a few extra yards and do some practice before attacking your beautifully stripped hull.

I think you can consider 3.75 oz as 4oz.

Sam