Brad,
I coiuld give a rats ass what other people think about Joes testing. I have done my testing, jay has done his....... and well, I dont like machining copper. Its a pain in the ass. Aluminum is much more suited for this work. I may stop the copper blocks all together. Who knows.
Btw Jay, I am happy to see that some of my advice worked for you, its all about helping each other. Now lets see some pics of your mill setup. Btw, the watercooling your spindle moter, That is a good idea, HEHEHE I have my aircompressor cylender watercooled. Keeps the condensation down in the tank.
Great minds............ followed by something else.....
Jood work, Btw is the rubber seal holding up?