- Joined
- Dec 20, 2012
- Messages
- 9,422
It seems you don't see the correlation between MMR & tool pressure, so regretfully I will resist looking for simpler examples to explain this.
Okay, I knew there had to be some engineer-type guy out there who could explain things better. How about this:
If the machine tool’s spindle speed remains constant as the parting tool moves to the center of the workpiece, the cutting speed will gradually decrease until it reaches zero at the center. A decrease in cutting speed is disadvantageous for the tool and can severely stress the cutting edge. As the edge approaches the center, pressure increases as the tool is fed at the decreasing cutting speed. In CNC lathes, the control increases the spindle speed as the tool moves toward the center to maintain the same cutting speed. Eventually, however, the machine cannot go any faster and the cutting speed decreases as the tool gets close to the center of the workpiece.
Simple enough for you?