Re: Help?? CNC PCB Drilling Machine

Yes Jon, from the center out is correct. My dielectric fluid is tap
water plus a bit of permanent antifreeze for a wetting agent. I apply
the fluid from a 3 gallon plastic bucket through a needle valve and a
hose to drip on the electrode business end just to flush the "dust"
away. All I did was make a dummy do nothing bunch of islands in a
crude fashion by manually moving the board back and forth and
operating the up - down stepper with switches to try out the idea. I
found no shorts between islands which is what I wanted to test.

I don't intend to go any further here as I don't plan on learning
what you guys already know. My intent was to see what others think
and maybe someone will make a useful tool. Then too, perhaps the idea
is not worthy of the effort.

My EDM is a close copy of the Langlois one except for a few
simplifications ( light bulb instead of power resistors). I was in
touch with Bob Langlois and he agreed that it would be nice to do the
milling without the dust! He even suggested a method to try using a
multiple electrode pattern made up for a given board design. He is
very busy though on writing up the wire EDM.

Your opinions are welcome. Richard

--- In CAD_CAM_EDM_DRO@yahoogroups.com, Jon Elson <elson@p...> wrote:

> Have you actually done this?
>
> The obvious problem is that you'd have to work from the center
outward,
> so you could keep an electrical circuit to where the ground clip
is. Or
> so you use brushes or rollers to maintain contact with the board to
> complete the circuit?
>
> Do you use a dielectric fluid, or do it dry?