TABLE OF CONTENTS When viewing a typical CNC lathe, the machine left side, where the chuck is located, is called the headstock. Opposite, at the far right side of the machine, is the tailstock. Its design and purpose has not significantly changed for many decades, although it has acquired some modern features tailstock is a part supporting device. In order to function properly, a small center-drilled hole has to be present on the front face of the part. This hole has a 60 angle that matches the supporting live or dead center, located in the tailstock.
Typical tailstock on CNC lathes consists of the main body that houses the internal mechanism, an extendable quill, and a tapered hole in the quill that can accommodate a live or dead center, depending on the tailstock design.
From the programmer s perspective, there are two types of tailstock:
Fully programmable tailstock ... both body position and quill are programmable within a range
Programmable quill only ... only the quill is programmable body must be set manually
If available, each operation requires a pair or miscellaneous functions (M-functions). For the fully programmable tailstock, there are four M-functions (examples only shown check machine manual):
Tailstock body forward ... example: M12
Tailstock body backward ... example: M13
Quill forward ... example: M21
Quill backward ... example: M22
For both types, the CNC operator is responsible for proper setup of the tailstock (body and quill).
