I love this stuff!

Posted by LeeG on Jan 28, 2006

Bob in the other thread should look at the numbers on carbon/glass panels.

I wonder if the early failure for the s-glass test panel compared to the 5oz e-glass panel is a similar thing to the carbon test panel. Before failure it actually had less deflection and was stiffer. Maybe there's a correlation between core material and skin characteristics that are optimum? It would be interesting to see those layups on 3mm ply.

The thing that surprises me,,looking at the photos of the fine weave 5oz and fine weave 6oz s-glass is that although the fine weave e-glass had a higher failure number the damage to the underlieing panel looks greater with the fibers and wood fracturing over a larger area.

That's the same thing I observed using regular weave e-glass and s-glass with crude backyard three point bending and whacking. Punctures resulted in shorter propogation of damage. There's also an elasticity to s-glass that's not apparent in e-glass or carbon. On a panel with 4oz s-glass on either side it would bend into a big c curve without shattering,,the threads of the cloth were full of parallel white fractures and the underlying wood was cracking but nothing broke through. With the 4,6oz e-glass the panel would break in half.

I should re-read the test but was there a determination of the effects of thick fill coats on strength? My sense is that there is a structural aspect to them. It's easier to peel up a well squeeged piece of glass than one that's got a few fill coats on it.

Ok,,here's the test I'd like to make,,3.25oz fine weave over 4oz regular weave s-glass,,just because.

In Response to: Re: nothing like testing by Mike on Jan 27, 2006