Esther & Fester Bestertester wrote:
See no n.g. for adhesives & epoxies, so if there's a better forum for this,
just point me to it.

I need an epoxy that is strong to the point of brittle. I want no flex; it
has to transmit vibration as close to 100% as possible.

Am I looking for a high Shore Hardness value? That's what Devcon uses in its
data sheets to specify hardness.

Is this something that I can achieve by changing the mix of the 2 parts? If
so, what do I lose if I use more hardener?

Any personal experiences with epoxies that you found to be harder than
others?

Filled epoxies (loaded with various mineral and glass bits)
are much more rigid than plain epoxy. But if you start with
a slow cure epoxy (30 minute versus 5 minute) the epoxy,
itself will also be a lot harder. Glass micro spheres are a
good filler if you want to lower the density, and glass
micro beads or aluminum oxide if you want to raise it. Even
adding talcum powder adds to the rigidity, but the gas
bubbles it entrains lowers it (foams are less rigid than
solids of the same material), so vacuum degassing increases
the rigidity.

A very rigid mineral filled epoxy is Hysol 1C:
http://www.gluguru.com/Hysol%20Data%20Sheets/1C.htm

A slighter harder aluminum filled formula is Hysol 9434:
http://www.gluguru.com/Hysol%20Data%20Sheets/9434.htm

But they make lots of variations:
http://www.gluguru.com/HyEpSelecGuide.htm

--
Regards,

John Popelish