On Monday 20 August 2007, Stuart Stevenson wrote: >Gentlemen, > I asked our EDM operator what parameters he would use with your >setup to get the 6/32 tap out of the steel. He set it up in our >LeBlond Makino EDNC 65. His recommendation is 30 volts DC, 1 amp and >10 rpm, dry with compressed air.
Compressed air has a logistics problem, the holes are blind. What was he using for electrode material? ATM, 3/32" brazing rod, no wobble so its boring about a .094" hole if I don't make it wobble, and its looking as if I should put in about 5 thou. The original holes were .110". >The fluid, whether it is dielectric >petroleum products or DI water is not for lubrication or cooling. It >is to solidify and flush the evaporated metal away from the arc area. Understood. In playing tonight with 25 volts & probably 100 ma average, I found that spinning the electrode at around 1k rpms seemed to add enough agitation to the oil that I could use it all up and go about 30 thou before I had to vacuum it out and refresh it, with about 1/2 cc in a modeling clay dam around the hole. A 100 rpm spin would short in just a thou or two. >Air will do that just fine and better than a puddle of oil or water. But how to get it to the bottom of the hole, which for one tap, may well be more than 3/4" deep, the hole was about done full depth of the tap when it broke. The one I'm working on first is maybe 3/8 deep, it broke on the first entry stroke. > You should probably try both polarities to see which is more >effective for your setup. It will make a difference. He just didn't >know which would work best. ATM, the workpiece is positive, insulated by formica in the vise jaws. If I get a different supply rigged, more volts basically, it will be isolated and reversable. >thanks >Stuart Thank You! -- 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) Nothing is ever a total loss; it can always serve as a bad example. ------------------------------------------------------------------------- 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
