for those curious, here's some interesting fodder:
i just got done PARALELL slicing my huge social circle , ga slice. as i did not need that much of it and wanted to sell some to defray cost, i also wished to retain a COMPLETE slice for my collection. so i took the big slice over to http://www.atlantaedm.com and they said that they could do it. we thought about using a magnet to hold the unusually- shaped piece, but we decided to balk on that as we were afraid that the powerful neodymium magnet would mess up the computer in the $250,000 charmilles edm machine or that the voltage through the wire would demagnetize the permanent magnet and the piece would drop, etc. we opted for a vise instead. we clamped it on one end and the wire was to start in at the clamp, turn 90 degrees and continue through the slice and out the end. $200 and 6 hours later the job was done- a perfect, lengthwise bisection on the slice accurately paralell to the finished surface to 15/1,000th of an inch. i wound up with 3 pieces and with loss of only 15/1,000th, it was so not an issue. what we learned about cutting iron skyrox on edm:
plan on ALOT of wire breaks- the magnetite/ rust rind is NOT nearly as conductive as the rich metal interior and it BREAKS the wire as there is no abrasive action (it is all eletric spark vaporizition- like millions of tiny lightning hits along the wire surface to the meteorite surface). to do it right, you first need to grind the rim down to the silver metal to avoid breaks. with that done you can pretty much walk away from it and come back when it is done. this process also takes place UNDERWATER- rusters need not apply. TROILITE is also a wire breaker as it too, has a different electrical conductivity. the FINISH is a very smooth, unusually FROSTED, colored surface with rainbow tones from the burning (similar to color/ tecture of heat-tempered file handle, etc.). this is easily buffed off w/ 600# sandpaper, and does not affect the etch pattern. the ACCURACY is beyond what any
abrasive saw could even hope to deliver. the COST is very high and the TIME is very slow. that should answer most q's about this unusual method of cutting irons. i will take PIX of all piece b4 etch for those intersted.
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