proximity sensors

[Moonhill Woodworks]

24 hrs ago my proximity sensors were working. Went in today to try maiden voyage of first real project. PRT Alpha 48 x 96. my proximity sensor on X is always lit up. Y won't light up at all when it hits sensor bolts. Checked all my wiring, everything looks correct. Any ideas? could it be a grounding problem?

[dana_swift]

wave a steel wrench or screwdriver in front of the prox switch. Is it working at all?

How large is the gap between the prox switch and the bolt head? It should be the thickness of a business card, no more, no less. (Grind the hardness indicator nubs off the end of the bolt head so its flat.)

The prox switch SHOULD work with a larger gap if it is in the air. Instead its mounted in a lot of metal, and that reduces its rated sensitivity. Be sure the bolt NEVER hits the prox switch, or that may be the last time it ever detects anything.

The prox switches will trigger at a reliable 0.002" repeatable position when they are set up right. Check both bolts at each end of all of your prox switches.

Good luck-

D