EDM Machine Questions

[coltac]

Hello everyone,

I have a small business making dies for bullet making. I was milling around the internet the other day, and ran across this Sinker EDM machine, and was wondering a few things about it. I will be "drilling" or i guess "burning holes into tool steel. Between .224" and 458" in diameter... I was wondering (in gereral, im sure there are many variables like fluid, or electrode material) how long will it take to burn a 1.5" x ..308" hole? I was also wondering if i could make my own electrodes. Im sure that they use pure copper or some king of copper alloy. Also maybe graphite? But i will be using copper if i get this machine. I can make the electrodes on my CNC lathe, and im assuming i can make a bullet shaped electrode so the finished hole is the same shape as the electrode. So, my questions are, how long, and can i make my own custom shaped electrodes to work with a sinker EDM machine. Many thanks, and looking forward to hearing an answer!

[jaredg]

Tool steal will go quick on a RAM edm. I burn that stuff all the time. If you are going .308 deep I would suggest 3-4 burns depending on the reduction. I use a mill to make my electrodes. You can use a lathe but just make sure that when you mount the graphite blank and machine it on the lathe that you keep it in the same holder being used on the EDM so you have good concentricity. PM me for more help.