:
: and Im trying to keep the weight down, anyone used 3.75 oz weight and put
: a little extra glass down the keel line. Im not going for bomber strength
: here. Any Idea how much # that would save

My understanding is that the weight of the cloth is the weight per square yard, i.e. 6 oz 'glass = 6 oz. per square yard...so figure out how many square yards of cloth and tape the boat requires, and multiply by the difference in fabric weight(s) to determine the difference in total fabric weight between various alternatives of 'glass and tape.

For weight savings in epoxy, the ideal ratio of the weight of the fabric and the weight of epoxy is 50:50 if the lay-up is done by a skilled person, i.e. 1 square yard of 6oz glass requires 6 oz of epoxy. For a klutz like me, I probably apply too much epoxy, and the ratio of epoxy weight to fabric weight is more like 60:40. So if you determine the weight savings in fiberglass by going to a lighter weight 'glass, you can determine the comparable savings in epoxy weight, also.

Hope this helps,

John