Quote Originally Posted by totts View Post
Not quite sure what you mean there? Would it be a good idea to add a plate to the back of the column and fill it with resin, or concrete?

Steel it is then! Cheaper too! Does anyone know the realistic weight of a 2.2kw spindle?

I will hopefully be goin to have a bt30 cartridge and motor, but i suppose it wont be too difficult to change the stepper motor of needed in the future.
He’s talking in terms of adding strength to the machine and he’s right but I was really referring to eliminating resonance more than anything, I can’t see that adding ribs/reinforcing plates wouldn’t add extra strength to the column, I think they would help towards stopping any twist in the column at the very least.

I think the problem with concrete is that it’s relatively brittle (though I note your suggestion of using rebar), cracks could form in the concrete and over time it may break down inside the column, I don’t know enough but I’m guessing that it doesn’t really have the same dampening properties as other materials, epoxy resin is a favourite but so is kiln dried sand and the sand is cheaper in comparison.

I think what I will do with mine is to, reinforce the column on the inside, use a mix of aggregate (different sizes, type 2, pea shingle and so on) to then fill the column, then backfill the lot with epoxy resin (filling up the leftover voids) all the way to the top, hopefully creating one solid mass. The idea being the aggregate is just away to use less resin (cost vs. cost) but also brings back the properties of using sand.

.Me