Z Home failed on start up- switch got snapped

Tonight I double checked everything finally pulled the trigger on the software.
X, Y and Z responded manually, but had to loosen up the Z acme and wheels a bit.
then I tried to home the limit switches and the z kept going up until it broke the switch and dead headed- so I killed the power.

Bad switch?

This simple mod with 22mm bolts will save your z limit switch in the future.

Bad switch, or bad wiring most likely. I had 10 cheap switches that I picked through. A couple were flaky.