[Mcgyver]

Larry, we may be onto something here

Our home made machines are growing in size, it takes ridiculous amount of time to weld these silly structures...

I had never thought of an epoxy granite structure as replacing a steel fabrication, its not strong enough imo, the yield stress is much lower than steel or cast iron irrc and the modulus of elasticity is about 1/6. saw it more as a way to stop a fabrication ringing like a bell. commercial practice suggests the same, where I have been able to see commercial uses for epoxy concrete, it is either filling the voids in a CI or steel structure OR use as a heavy base for machines deploying negligible forces, ie optical equipment. I would not make a metal working machine just of epoxy concrete, not unless a lot engineering calcs proved my assessment wrong. don't forget to normalize any fabrications going into a machine

Larry, we may be onto something here
Yes, some of these compounds have incredible properties (vs cast iron) but we're trying to solve some very "basic" problems here.

Larry you mentioned earlier 50X better than steel and 10x better than CI for epoxy/granite's vibration dampening abilities, seems high to me. I'd read CI is 1x better than steel and Epoxy granite 50% better than CI. Not that easy to find info on the subject though, after all vibration is a magnitude and a decay, its not straightforward, at least to me, what better means, but 10x seems high.

thanks for all the good info being posted on the subject, I continue to believe it holds promise for high end diy machines