Homebrew PCBs

We were even considering a rotating electrode and a diamond wheel  
"automatic sharpening station" back then.

Try graphite, they use it for EDM sinkers.

Probably a continous feed wire is easier than all that, but it would need  
to be pretty thin wire to get any decent resolution.

ST



On Tue, 02 May 2006 19:57:22 +0200, roger lucas <ralucas4277@...>  
wrote:

> Hi Stefan,
>
>
> I know that it should have worked in theory, but I was
>
> surprised at how well it actually turned out.
>
>
> I tried with tinned copper wire and a tinned steel
>
> sewing needle (purloined from my wife's needlework
>
> box), essentially the wear was about the same for
>
> both. The eroded pixel diameter is directly related to
>
> the electrode dia, as the sewing needle eroded the
>
> pixel became larger.
>
> I need to try to obtain some half hard or hard 10 mil
>
> brass wire for the next trial.
>
>
> The setting of the spark parameters before sparking is
>
> essentially to eliminate the uncertainty of whether
>
> pixels have been fully eroded or not, especially where
>
> electrode wear is high. I might just try some broken
>
> carbide drill bits, the tungsten might resist erosion
>
> better, trouble is carbide only goes to 0.5mm dia.
>
>
> Will post some sample photos after next revision and
>
> trials.
>
>
> Roger