CNC Sherline Lathe Project

[vedoula]

It looks as if it is increasing the cut depth the same amount each time through. which can be a problem if threading harder material like steel. Optimally you want the cut depth to decrease as more of the tool engages the stock.

kvom, is this because you want the volume of metal removed each time to be the same -- rather than the depth of the cut?

v

 

[kvom]

The deeper the cut, the more of the tool tip is cutting, and thus more force. It's like any other turning operation, too large a DOC can break the tool tip or stall the motor. So cutting the same volume per pass is what you want.

For Mach3, G76 is the canned cycle. The H code gives the depth of the first pass, and the control figures the number of passes and depths for constant volume removal up to the Z code depth. EMC may have something similar.