A machining tool assembly is provided for machining a blank to form a firearm lower receiver. The assembly includes a pair of side plates positionable on opposed sides of the blank to capture the blank therebetween. A template plate having a template aperture is adapted to be removeably attachable to the side plates. The template aperture is aligned with a top surface of the blank and is adapted for machining a cavity within the blank having a peripheral contour complimentary to a peripheral contour of the template aperture. A centering mechanism is adapted to be removeably attachable to the template plate, with the centering mechanism including an opening aligned with a corresponding void formed on the blank to align the blank with the template plate.

Disclosed are a setting method and a control device of a depth of cut in an initial axial direction for a rotating cutting tool. A setting method of a depth of cut in an initial axial direction for a rotating cutting tool according to the present disclosure includes when a tool T is mounted on a spindle S, receiving an overhang length L of the tool T, the diameter D of the tool T, an overhang length ratio reference value C, and an axial depth of cut reference value E; calculating an axial depth of cut Y; and setting the axial depth of cut Y as an initial axial depth of cut of a cutting process.

A milling device for a grinding ejector pin machine provided by the present invention has a cutter seat, a sleeve, a milling cutter, and a pedestal. The cutter seat has a push rod and a spindle, wherein the push rod has a first accommodating space, and the spindle is located in the first accommodating space. The sleeve is hollow and located at one end of the cutter seat. The milling cutter is connected to the spindle and located in the sleeve. The pedestal has a collar, a stroke adjustment device and a ball mill head, the collar accommodates partial of the push rod, and the stroke adjustment device is at one end of the collar.