On Tuesday 21 August 2007, Thomas J Powderly wrote: >air ir s bad dielectric, it forces you to get much closer to the work before > the disharge occurs use a 'parrafinic' like kerosene. > >connect your air to a 'paint pot' full of kerosene and get a brass tube >you now have high pressure flush > >rig up a holder to chick up one end and a hole in it to connect the tube at > the other drill a cross hole to admit the pressureized fuild >connect the power to the tool with a jumper clip >(i doubt youre' achieving much current, so little heat ) > >work submerged, like 1" submerged `( dam or tank ) > >whatever cap you use it is best to have a longish (several mS ) non sparking > time since you use a cap ( not a n osccillator ) you dont have independant > on/off so use what you have > >aim for consistancy not speed >the speed you get with a consistant cut is the best speed >screwing with it for several days suggests you dont have any consistancy > >commercial edm hole drill rotate fast to make the end wear even, else you > get pointy and pointy is a hot spot >and a hot spot slows you down > >commercial units use thru flush at > 800psi head >the end flow is low, but the swarf build up requires it ( lotsa flow) >if you dont get the swarf out, you're cutting swarf > >use a spit shield because this can splatter a lot > >alumatap is good smells nice but is darn expensive >kerosene is cheap >both are highly flammable, so submerge >( removes air, reduces fire potential until the fluid is hot enuf to > ignite... np for you) > >capacitor discharge ( and lcr types ) are so old i have no data on them >old AGie STM STDM VF generators had such, but that was 1960 >if you could guess from this rough idea from a transistorized system...... > discharge time of 32uS longer just heats soft tool too much, cause > more wear not more removal off time >400uS this is chip > clearance edm is like a bandsaw, on=tooth off=chip clearance average > discharge voltage 50V you'll have to sand back further than the pros > supply voltage near 100V= the discharge will be near 30V= (seen on > scope), you need higher to 'start' the spark with a single supply, use a > higher open/noload voltage > >and 'lower your expectations' ;) > >tomp
Thanks Tomp. Higher voltage and amperage on order. -- 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) Linux: Where do you want to GO... Oh, I'm already there! -- Ewout Stam ------------------------------------------------------------------------- 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
