Elrod Z-Axis Drive ballscrew disconnect switch

[tblough]

For any others here with an Elrod Z-Axis drive, I recently replaced the ballscrew disconnect microswitch with a Metrol precision limit switch and couldn't be happier. The stock Microswitch is very touchy to get adjusted correctly to sense between clamped and unclamped and I often ran into problems with rapid Z moves causing vibration and subsequent false triggers of the switch causing my program to abort.

I ended up replacing the switch with a Metrol CSJ055A-L touch switch that has 5µ repeatability between open/close. It is much easier to initially adjust and the false triggers are now history. The CSJ055A is a NO switch because now it senses blocked clamped whereas the previous NC Microswitch was sensing block unclamped. This is actually an improvement as well because now broken wires or switch failure will cause the control to inhibit automatic z-movement.

[martyscncgarage]

Thanks for sharing that Tom!
Looks like a nice kit. Care to review?
Marty

[Muzzer]

Presumably you had to remove the ballnut yoke to machine it so the new switch would fit. Which probably involved removing the ballscrew assembly too?

I made a similar yoke for my Bridgeport but I doubt there is enough movement to detect it with a switch - there must be a lot of slop on the Elrod part when loosened off.

[tblough]

@Marty - I've been impressed with the kit. Actually took measurements and duplicated it for my home mill. Elrod recently sold his CNC business to Servo Products. It will be interesting to see how that works out.

@Muzzer - yup. The ballscrew needs to come out to remove the ballnut block. The ballnut block split, clamped with a -0.004" spacer, and then bored. It springs open .004" when unclampped, and is on-size when clamped.