MetalworkingFun Forum

In Dr Stan thread, about locating a milling machine head, he mentioned he wanted to increase the number of speeds on his Fray milling machine, I said I would post some picture of how I did it. I wanted to leave the machine as stock as possible, so I made a "transmission" insert, to remain single phase, for the both the Jet JVM 836 and the newly acquired Rockwell milling machines. I know I could have gone with a 3 phase motor and a VFD, but I didn't to incur the cost (motors and VFDs), and as most of the pieces were either already on hand or were very cheap to acquire.

On the Jet JVM 836 I went from 5 speeds ranging from 250 to 1500 rpms, changed to 25 speeds, ranging from 48 to 1550 rpms.

Good job.    BTW, that's right there with my plans.

On the Rockwell mill, I did a similar insert or cartridge style piece to raise the number of speeds from 6, ranging from 370 to 6300, with the change, the mill now has 24 speeds, ranging from 125 to 6650 rpms. The motor mounting is still a work in progress, but the mill, even in it Mark 3 mode, is a joy to use.

Typical ingenious and well-crafted projects, Jack !