Zaxis endstops

End-stops for the Z axis

Whenever you label a design with something like "Universal"  Endstop Bracket your asking to be taught that nothing is "Universal". Such was the case with designing Z axis end stops for my OX.
I needed a micro-switch on the top and the bottom of the Z axis's travel. There was no place to mount the simple "universal" brackets up in that very busy Z axis mechanism.

Since these brackets were essentially made on the fly, lots of trial and error, I do not have drawings for them. The parts were made from both .093 and .22 acrylic and bent on a shop made hot wire bender. Oh, and a dab of superglue here and there.

Down End-stop

The down end-stop is mounted on the upper Z channel top plate just below the Z stepper. I wanted to mount it on a stationary part of the mechanism and let the switch be activated by the moving axis. That approach eliminates wires having to move but there was no room. So I ended up moving the switch and as a result this switches wiring will have to be routed in a moving loop like the stepper.
The down end-stop interposes the lower roller plates as it moves down.


 
The down bracket. The switch mounts have slots for fine adjusting the stop position.

Mount of the down switch bracket. There is a clearance hole for the stepper spacer but it helps to keep the bracket from rotating. The left 2x holes are for cable ties.

Switch mounted and adjusted by moving up and down in its mounting slots. Interposes the lower roller plates.

Up End-stop

The up end-stop was much more complex to imagine and make but it is mounted on a stationary part of the assembly so the wiring does not move with the Z axis.
I tried something new in acrylic bending. Note the mounting arm for the switch is a feature of a one-piece bracket. The arm was formed on the hot wire bender :).

Single piece micro-switch bracket. The switches mounting is fixed but the bracket can be moved up-down (slot) for adjustment.
Bracket mounted on stationary side of axis. Cantilevered across to sense position of upper plate.

Showing both end-stops. Up on the left and down on the right

Up end-stop switch integrated (CA) with the breakout and spindle driver package

A complicated hack! Could use a simplification redesign.

Enjoy and comment,
Don



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