Dampening Tools Internal back-turning: a new possibility to increase productivity
“Back-turning” is not new, but interesting and can increase productivity substantially when making “internal back turning”. MAQ explains how this method can be used to increase machining productivity.
Just like the “G0” NC code, experienced machine operators are fond of making back-turning to reduce machining time and increase the tool life, measured by the number of workpieces. When it comes to internal turning, a back-turning, with roughing in forward and finishing backward, can reduce the number of tool changes and increase the duty cycle to save cost. However, back turning has its challenges when making internal turning operations.
A back turning operation in internal turning will use two different lead angles, and the lead angle has a detrimental effect on the vibration of a cutting tool. The figure below makes a relative illustration of the vibration tendency in a machining operation with forward-turning and backward-turning.
In other words, back-turning demands high-performance damped tools in internal turning operations.
The MAQ vibration damped tool holders have a wider operation window, which in this case gives the possibility to have a wider selection of “Lead Angle”. In the given machining example, we made a forward turning to make a roughing operation with a 1 mm depth of cut and then a finishing operation with a 0.1 mm depth of cut and as you can see the result is excellent.
Choosing MAQ products brings operators more freedom to plan their machining differently to save time and money. It is possible only because of the STMD technology that automatically adjusts itself to the working condition.
If you are planning to try back turning, MAQ’s advice is:
- Use a V shape or D shape insert which directs the cutting force in the longitudinal direction, such that the vibration tendency is less.
- Use a depth of cut smaller than the nose radius of your insert when making back turning.