Homebrew PCBs

Stefan Trethan wrote:

>Electrode erosion is quite normal with EDM, it is not a fault as such that  
>can be eliminated.
>
>Probably can be reduced though..
>
>  
>

  Yep hadn't thought on it in a while, but doesn't look like much you 
can do beyond having the electrode negative and spark power etc.  If 
only you could keep the electrode very cold and the board very hot for 
different vaporization energies, but wouldn't be easy.  Heck wire is 
cheap anyway..

  Your wheel got me thinking on a disc, a thin copper washer on a Dremel 
arbor would have much larger edge area.  Spin it some and it'd last a 
long time with little change in gap, a little less precise in the long 
direction but that's the way of travel.  But directional, wire isn't, 
and again heck it's cheap make a feed system and throw more at it.  .2mm 
pencil lead might be an option too on the graphite end of things..


  For this, an HP Plotter may be a good choice too, no real need for CNC 
power.  HPGL is so flexible you may even get to the low feed rates 
needed just from the language..  Of course I just threw mine away with 
the older inkjets in the last round.  Useful but way too bulky when not 
using, and easy to replace for $10 or $20 here or there.  Didn't even 
junk them this time, too much work for a few motors.

Alan