View Full Version : Zero plate clamp closes circuit anytime it touches the bit (or machine).

09-04-2006, 07:58 PM
I am so close to being up and running. This is my last thing to do.

This doesn't make sense so I'm hoping someone else has tackled this problem. The clamp for the zero plate completes the circuit as soon as it touches the bit. Note that the zero plate and curly wire is totally insulated from touching any metal on the machine. It is resting on the MDF, nowhere near the bit(or any other metal). No bare wires touch the CNC, yet the clamp can touch anywhere on the machine and close the circuit.

I figure the problem must be in the control box. I'll run some errands and come back to this later. If anyone has an idea, please let me know.



09-04-2006, 09:18 PM
If I were puzzling this... Unplug your Zero plate wires from the control board. Use a continuity meter and verify that there is not a short anywhere in the wiring. Once satisfied there is not a short somewhere, reconnect and test once more. If it still occurs I would manually jumper some wires from the control board replacing the Zero plate wiring with my own temporary test wiring and test again.

Just thinking through it in my head, but verifying the wiring harness does not have any shorts would be a priority.

I know how you feel, when I got mine setup the E-Stop button was always on. Turned out to be a jumper on the board set incorrectly. So, if you are really wanting to get started you can Zero Z manually. Use the keypad in short bursts to get close, then zero z. You can atleast have some satisfaction of cutting something.

I suggest cutting foam on your first few tests. Even with the spindle off it slices the foam without breaking it... don't ask me how I know that.


09-04-2006, 10:24 PM
Try reversing the wires for the Z zero plate in the control box once . I think I had that same proplem when I first got my bot . and that fixed it .

09-04-2006, 10:38 PM
OK, I forgot that the Z plate shares the ground with the prox. switches. It took 30 seconds to figure out the problem once I saw that. The prox switches were grounding the z plate. All I did was switch the white and black wires (for the z plate) in the control box. Everything works. Tomorrow I may try to make some sawdust.

Thanks for the post Robert. I didn't see Stephan's post until after the problem was fixed. Thanks as well. This is where it gets fun.