Re: Cast resin for a cnc mill design - good idea?

--- In CAD_CAM_EDM_DRO@y..., "Smoke" <gordonr@r...> wrote:

> I looked into this once. The company I researched that does it
> uses a mixture of silca and castable poy.

Poy? Like the Hawaiian stuff? :)

> the minimum "grit" size for the "silica"
> is 1/2" diameter. After reading the info at the site, you find out
>the "silica" is actually rocks...

> The molds are custom made for each project and are EXPEN$IVE!

Thanks for your input, Smoke...
Remember, this would be a small mill. Large grit (or rather, ROCKS)
would be out. I wouldn't want to "shake-down" a thick mass of resin
and rubble. I'm thinking perhaps powdered stone or metal.

A mold or two for a small mill wouldn't be that much trouble...
(possible famous last words).

> Another disadvantages to using resin (I've tried it) is that it
> isn't anywhere near as strong as aluminum or steel, consequently
> web cross sections need to be much thicker.

I don't think that would be much of a problem with a small mill,
especially if there was a metal sub-structure embedded within the
epoxy.

I haven't considered lost-wax casting. That is an interesting
thought. Burning out the wax in my kitchen probably won't go over
well with a certain someone, though...

Tom Murray