> Don, what prompted your post about lamination failures. Perhaps I missed
> the discussion. I'd like to hear more. What glass/epoxy combinations are
> failing?

> Jim...

I posted an earlier question about delamination of Raka 3.25 oz fine weave, to which there were several responses. I looked in the archives but did not see it. From memory, most of the other responses had to do with the fine weave not being quite as strong a bond as standard 4 oz cloth. I did subsequent tear test on a scrap of plywood, which bonded better. Also, with the weave filled it bonded better. Net result, for me, is that I wont use the fine weave cloth again. Several other builders agreed. That's not to say Raka is not a good company. Several people use thier epoxy, and I will not hesitate to buy 4 oz cloth from them.

I also recall several discussions between George and Nick, as George correctly points out, regarding strength. My summary is of two philosophies here - one in which design work and limited testing is done to reduce weight, and another in which enough of a safety factor is used to prevent all but catastrophic failures. I think both are valid, but there is no conclusive test data out there using different cloth lamination on the same wood, to really base any good information on. My long-winded point here is that it is high time for the testing to be done, and that only one with the lab recources and/or financial backing to pay for it is capable of doing anything really useful. I suspect that the epoxy manufacturers have done some, and are possibly not willing to share the results?