Properties of reinforcement fibers

[Alex]

First test results with Basalt UD fabric:

I created two test pieces - 5mm wood strips one with 220g/m2 UD Glass above and below the wood and one with 240g/m2 Basalt UD below and 220g/m2 Glass above the wood (as Basalt has no advantages in compression).

The basalt/wood/glass sandwich is a bit stiffer (as expected by fiber properties). What is really awesome is the dampening of that sandwich - big advantage compared to the glass/wood/glass construction!

[davide]

What do you mean by dampening? Does it sound more low pitch than the glass sample?

[Alex]

Uuups - wrong word

I meant damping (vibration absorption). I tested with the two strips clamped at one side, bending them and suddenly removing the force. The strips oscillate with decreasing amplitude.

The Basalt composite shows a much stronger reduction in amplitude over the time.

[davide]

Thanks, that is what I was asking. Actually I did not notice your mistake...

If you have an pick-up (electric guitar) around you can attach a pice of iron on your strip, and use the pick-up to record the oscillations...

[Mud]

Just in case anyone is looking for a distributor of Zylon or Basalt/carbon fabrics, here you go:
http://www.sollercomposites.com/
They also have unidirectional carbon tape, which I have had a hard time finding.

[teleman36]

Just a little input on zylon as a dampening composite. I like it and seem to be always choosing to ski on the skis with either 1 or two layers of zylon built in. Have not done any scientific testing other than skin it. Very tuff stuff. I use a layer just above the base inside the trough between the edge tabs thinking that would prevent core shots, and a layer above the core as well. A bitch to cut, but am buying a self sharpening shear to deal with it. And for all the old farts out there, the zylon under a natural topsheet looks just like the old Rossi Strato burgundy color. I also highly recommend soller composites. Jon is very willing to share information, tricks and techniques, has good prices, ships same day. They also have shearing capabiliies so you can tailor your materials to suit your needs.

[davide]

...the zylon under a natural topsheet looks just like the old Rossi Strato burgundy color...

Zylon does not like light, it deteriorates the mechanical properties... Better keep it in the dark.
In addition is not very strong in compression, so it is better to keep the bottom layer only.