The rotary broach is a marvel of modern machine tooling. This cutting tool allows machinists to add internal hexagon, square and other forms to precision metal parts. The modern machine shop can benefit from the quick set-up and ease of use available in adjustment free broach holders. The GT Series broach holder available from Polygon Solutions has been designed for this purpose, and often eliminates secondary operations.
The single pass broach is held on center in the holder at a one degree angle. Thus, the full force of the machine is directed to the cutting edge closest to the part. Since this is a turning operation, the cutting action will rotate to every edge, and as the tool is fed into the pilot hole the desired depth is achieved.
The GT Series rotary broach holder requires no centering, indicating or alignment procedures. The broaches are cut to a specified length. When fastened into the holder the broaches are designed to be on center with the pilot hole. A small amount of endplay insures that the broach will follow the chamfer of the hole.
When broaching a blind hole, it is possible that hydraulic pressure can build up due to air and fluid that may get trapped inside. Polygon Solution’s rotary broaches and GT series broach holders include a pressure relief hole to eliminate hydraulic pressure. Air and fluid are pushed through the hole in the broach, and then can escape through the hole in the broach holder.
The GT Series rotary broach holder is available with two different spindles. One spindle accommodates 8mm shank broaches, and the other holds .500” shank broaches. Although the 8mm broaches may cost a little less, the .500” shank broaches are available in more sizes. Rotary broaching is ideal for forms within this size range.
The bearing configuration of the broach holder is designed to handle the loads associated with rotary broaching. The sealed design requires no maintenance or messy grease guns. Help with speed and feed rate is available from Polygon Solutions.
Rotary broaching will work on most machines with spindles, including lathes, mills, and machining centers. Different shank sizes to fit into your machine are available in metric and inch sizes. Dimensions for the tooling envelope are available online.
The GT Series rotary broach tool holder from Polygon Solutions represents the pinnacle of “on machine” broach tooling in today’s machining world. Standard inch and metric hexagon and square broaches are available for immediate delivery. Technical support, broaching data, and information about the tool holder rental program are available online at polygonsolutions.com.