I was just wondering if anybody has a Jet JVM-830 knee mill that they have converted to cnc. I picked one up from a guy about 2 months ago for 200 bucks. It needs a little attention but it was well worth it. I am going to be replacing both the X and Y lead screws with ball screws, because the screws and nuts are very worn and allow slop in the middle of the screw, but at the end it is so tight that it takes 2 hands to turn the wheels. If anybody has any advice on what size motors to use that would be useful. I was looking at these servo motors (http://www.surpluscenter.com/item.asp?UID=2007122009120221&item=10-2351&catname=electric), which just need encoders. I believe that they are the same ones that lowcostcncretrofits.com (http://www.lowcostcncretrofits.com/servo%20motors.html) sells, but without encoders. -Adam

Anybody have any advice? Also I was thinking of whether I should convert the quill or the knee part of the mill. I have read about using gas charged springs to counter balance the knee and allow you to use it as your z, giving you a larger z height. Any suggestions I would really appreciate it. -Adam

It has been awhile, but I never got an answer. I am starting this project real soon and am looking for some advice about how I should go about it. I also need to replace the screws and nuts, because they are totally worn out. I was looking at going with roton ball-screws. Any suggestions? -Adam