Substitute for Bridgeport Power Z Axis (Knee) Feed

[Tmate]

Since a Bridgeport knee moves only one inch up or down in ten turns of the crank, moving it up or down 6 to 10 inches or more can be tedious. Small, precise movements with the crank are fine.

For those times when a power assist would be helpful, I bought the attachment shown in the photos ($45 at http://www.snrmachine.com). Just chuck it up in a 1/2" 18 volt cordless drill on low speed, and you can move the knee up or down a foot or more in seconds. Just get it to the approximate desired location, and fine tune it with the crank. It also reduces the temptation to lower the quill for milling, rather than raising the knee.

When not in use, I hang it on the back of my VFD support column.

 

[jwmelvin]

Making one of those was my first project with the knee mill. Definitely better than hand cranking.

 

[mmcmdl]

I made one years ago . I was telling Aukai you don't need a power feed unit on the knee the other night . I hope he reads this thread .

 

[ttabbal]

I use a 3d printed version. If I run it too far, the plastic snaps. I guess it's kind of a fuse, not breaking my drill I guess. Kind of annoying when it happens though.

 

[jwmelvin]

If you have a rotary table (or indexing head) it’s not a hard project. It’s not like the fit has to be all that perfect. I made mine in two pieces just to accommodate the materials I had around.

 

[Aukai]

You have to have the knee mill first to use it