Polygon Solutions Inc. designed the broaching brake to be used as an attachment to its innovative GT Series rotary broach holder. The brake mounts to the tool holder using set screws. Additional screws are included at the opening of the brake to gently tighten against the spindle. The broach is fastened into the spindle, and must make contact and be aligned at the first hole.
When the broach is engaged with the part, the brake is loose enough to allow the spindle to turn without interfering with the broaching operation. Unlike typical rotary broaching operations, turning must stop before removing the broach. When the broach is removed, the brake screws are tight enough to hold the broach’s position until it makes contact with the part at the next hole.
The rotary broaching brake can be used to hold orientation for single or multiple parts. Tightening the screw to be loose enough to allow broaching, but tight enough to hold orientation requires patience and a level of experience. Some trial and error can be expected and the broach orientation will need to be checked at regular intervals. The hardware consists of standard screws and nuts that can be replaced or reordered easily.
The rotary broach brake is a simple device used to keep the broaching spindle tight enough to hold orientation, but loose enough to allow the spindle to turn while broaching. Some experience with rotary broaching is helpful to determine the right amount of pressure required. Will not fit GT-150-A or GT-150-B.
- Slide the brake onto the tool holder.
- Line up the spindle tightening screws to the edge of the spindle.
- Fasten the brake to the holder using the nylon set screws. Do not over-tighten.
Note: Using metal set screws may squeeze the body and damage the bearings.
- Turn the spindle tightening screws until the pressure on the spindle is relatively tight but loose enough that the spindle can rotate when in contact with the part.