Bridgeport Knee Power Feed
The Bridgeport knee power feed is a tool that enables a mill operator to raise & lower the knee with a power drill, both more rapidly & with less physical effort than would be required to do the same work manually. It consists of three components: a corded drill, a 1/4" hex -> 3/8" square socket drill adapter (pictured chucked in the drill), and the 3/8" square -> knee crank adapter.
An important note concerning safety: go slowly with this. It's easy to stall the motor by demanding more torque than it can provide, and furthermore, it's probably not a great idea to be running the knee up & down (especially down, given how the vertical ways screech) at breakneck speed. The power provided to the drill can be varied by varying the pressure with which the trigger is pulled.
|Where||Large Mill Accessories Cabinet|
|Host Area||Cold Metals|
To enable future modification, the 3/8" square shank in the crank adapter is retained in the adapter body with a 1/4" x 1" dowel pin: the square shank is machined onto the end of a short section of 5/8" OD steel rod, which fits loosely (but closely) within the 5/8" ID shaft through the center of the crank. By machining a similar such feature onto the end of a similar section of rod, drilling an appropriate cross hole, & replacing the square shank, any number of drive mechanisms could be supported.