On Aug 20, 2007, at 8:27 PM, Gene Heskett wrote: > On Monday 20 August 2007, Dave Engvall wrote: >> Hi Gene, >> >> Paraffin oil aka lamp oil is pretty close to EDM dielectric. > > How about fuel oil, as in what you'd feed one of those horizontal tank > heaters? It seems as usable as anything else & I've got 5 gallons > of it > getting old, cuz I fired it up in the shop one night several years > ago and > everything in the shop turned bright red with rust in about 15 > minutes. I > had no idea they put out that much steam/water vapor... Obviously > never lit > it again.
Stuff could be paraffin oil or kerosene. Used carefully it should work. It is pretty difficult to burn oils and not put out both CO2 and water. ;-) .... and if the burn is not lean the CO also. ;-( > >> Using >> 70 -90 V for your DC supply and something on the order of 10 uf >> with a resistor in the 20-50 ohm range should get you an RC circuit >> that will be close. A bit if component substitution will get you to >> an acceptable combination. > > With 25 volts, & 10 uf, lets just say that progress has to be > measured with a > micrometer, daily. I managed about 0.110" deep today. > >> The electrode really doesn't have to >> rotate, just pick one a bit larger >> than the core of your tap; erode out the center and tip the outside >> pieces in. It works like a charm. >> The higher voltage will make the gap adjustment much less critical. > > I'm looking for a suitable transformer right now. How about a pair > of these > at herbach? > Sure ... 78 V peak ... should do the job nicely. Using just one transformer will make the gap a lot harder to control. Those should give you plenty of current density ... you can always scale back with either smaller caps or larger resistors. > > With the secondaries in series aiding, that ought to be enough, > using one 50 > ohm 200 watt limiter R. > > Also, tonight I found that if the electrode spins at approx 1k > rpms, it seems > to stir the oil a lot better & it doesn't descend to a short > circuit nearly > so easily. I could got 30 to 40 thou on an "oil change", with > about half a > cc trapped in the modeling clay dam, which the oil dissolved > eventually. > >> HTH >> > Muchly, thanks. > >> Dave > > -- > Cheers, Gene > "There are four boxes to be used in defense of liberty: > soap, ballot, jury, and ammo. Please use in that order." > -Ed Howdershelt (Author) > Penn's aunts made great apple pies at low prices. No one else in > town could compete with the pie rates of Penn's aunts. > > ---------------------------------------------------------------------- > --- > This SF.net email is sponsored by: Splunk Inc. > Still grepping through log files to find problems? Stop. > Now Search log events and configuration files using AJAX and a > browser. > Download your FREE copy of Splunk now >> http://get.splunk.com/ > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
