nearly all the knee mills I run across make the quill the Z axis, the trouble with the knee it has a very large mass plus the load of the work peice, which makes a decent feed rate near impossible. Most just motorise the knee just for initial positioning, ball screws are the way to go for accuracy etc and when climb milling. There is a lot of difference with a motion control card, it is just quite a bit more expensive, I am spoilt I guess, as once you have used them, it is a job to go back.
Al
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CNC, Mechatronics Integration and Machine Design.
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E. |