Re: [CAD_CAM_EDM_DRO] EDM electrolyte

Carl Mikkelsen, Oasis wrote:

>I've thought about building an EDM (it was what got me started building a
>Stewart Platform), but I'm hung up on the problems of purifying the
>electrolyte, and disposing of the waste materials. The books I've read
>have suggested using ion exchange rosin beds, with its set of disposal
>problems.
>
>What are others doing?
>
>

For the tiny tap burning jobs I've done, I used Alup-Tap, a low vapor
pressure solvent-based
formula for tapping aluminum. it works, and I've only had one small
flash when the level
of the fluid got too low. It stains everything badly, but maybe that is
more the fault of the
tap material being reduced to molecular-sized dust.

Many others have suggested distilled water from the grocery store, and
using a once-through
system. An elevated can delivers the fluid through a small tube to the
electrode, and the
contaminated fluid just spills over the part.

If you are going to be making big mold cavities with a multi-hundred amp
EDM, then a
real EDM fluid processing system is required, but for a miniature
home-shop EDM, it
is overkill.

Jon