(Catching up on some posts I've missed tonight while waiting for some
sealants to dry)

EDM Machining is something I'd love to have controlled by on a Pic,
really...

It's pretty interesting stuff...  Been since 1980 or so since I had
anything to do with it so need to read about it more <G>

  Mark

Russell McMahon wrote:
>
> Mark,
>
>     Copied to PICLIST as there may be others
>     there with some knowledge of this.
>
> >The next hurdle after that is to drill some REALLY tiny
> >holes (like 0.005") for ullage vents, I REALLY am not looking forward to
> >that!  The flute drills are ~$7ea. and only come in packs of 10...I'm
> >positive that I'll be breaking a few of those(probably off in the work
> >:-(!)
>
> I haven't tried this but you may find that spark eroding is a viable method
> for such small holes and you may be able to make an eroder at lowish cost
> and without too much effort or electrical knowledge.
>
> I'm an electrical engineer but have only noted spark eroders "in passing". I
> believe they mechanically offer up a work-piece to the surface with an
> appropriate source of current connected. For a very small diameter workpiece
> the current requirement could be quite small to get a large current density
> at the contact point.
>
> It may well be that a capable plug pack ("wall wart" where you are I
> believe) would suffice or for a little more go a car battery charger.
> Perhaps add a large surplus capacitor to either for more initial current.
>
> I don't know the relationship between stylus area and hole size but I
> imagine the hole is "somewhat" larger. You may need something like an
> 0.0025" (0.1mm) dia stylus. This can probably be a "whisker" of high tensile
> wire. The ullage hole dia is probably not too critical.
>
>       Russell McMahon
> _____________________________
>
> >From other worlds - www.easttimor.com
>                                 www.sudan.com
>
> What can one man* do?
> Help the hungry at no cost to yourself!
> at  http://www.thehungersite.com/
>
> (* - or woman, child or internet enabled intelligent entity :-))
>
> <snipped>

--
I re-ship for small US & overseas businesses, world-wide.
(For private individuals at cost; ask.)