Page:Practical Treatise on Milling and Milling Machines.djvu/149

Rh

Gutting a Circular T Slot in Universal Milling Machine Saddle on a No. 3 Vertical Spindle Milling Machine

The operation shown above illustrates another excellent example of the use of the circular milling attachment in connection with a vertical spindle milling machine, for cutting the circular T slot in the saddle of a universal milling machine.

The piece of work is centred by placing it over a stud and bushing inserted in the hole in the centre of the circular attachment table. It is prevented from swinging by four bolts with washers, two of which are shown, and a strap from a stepped block across to the casting on each side fastens it to the table.

The first, or plain, slot is cut out on a boring mill or can be milled at the same setting shown above, using a two-lipped end mill, which is then replaced by the T slot cutter.