Z Probe now going opposite direction

amprops · August 1, 2025, 5:58pm

Hi all! Hoping I can find some help troubleshooting an issue that cropped up after a CNC failure.

For some background - I have run several successful jobs out of foam, mdf, and 3/4" ply using a variety of bit sizes, with EstlCAM to create my toolpaths. Everything was looking great!

I started a new project last week and I would say was 50 minutes into an hour long project when I had to step away to a different part of the shop for a minute or two to address another issue. I came back and found that the router had plunged into the material all the way down to the collet and the friction was creating a small fire. I’m not sure what happened, whether it was a software or hardware issue, but regardless that is not the issue I’m trying to solve right now anyway but figured it was worth mentioning just in case.

Jump to a day or so later when I have the time to remove the router, do some cleaning and checking of things, and reinstall the router. The machine jogs just fine in the X,Y,Z, in the correct directions, and nothing seems out of the ordinary. Upon uploading a new CNC project, I was prompted to place the z probe as usual and proceeded with the z probing. However, the Z was sent in the opposite direction, up up and away. I’ve tried double checking my connections, redoing the CAM file, and have double checked the values/texts/etc in EstlCAM to make sure nothing changed on that end (it hasn’t). I’m just finding it really strange that it moves in the correct direction when jogged, but not when it’s probing. Below is a sample of the .gcode before I have to use $! to stop it.

^and really just more of the same, with the third MPos value increasing until I can get that $! typed in^

Thoughts? Thanks again!

Bartman · August 1, 2025, 6:52pm

This has been said over and over again, but I’ll say it once more…

NEVER LEAVE YOUR MACHINE UNATTENDED!!! Even for “just a minute”.

Your insurance adjuster will thank you…

MakerJim · August 1, 2025, 7:22pm

Let’s see what we can do to get you up and running. First off the obligatory safety inspector comment. This wasn’t a CNC failure. It was an operator failure. Pause your machine if you have to leave it unattended.

Ok with that out of the way: What controller do you run? We need to re-test your limit switches and possibly your stpper motor wiring.

amprops · August 1, 2025, 8:18pm

Thank you.

I am running a Jackpot CNC.

MakerJim · August 1, 2025, 8:22pm

Alrighty. Let’s check your limit switches.
Power off your machine, SLOWLY move all axis so they are away from the limit switches.
Power on, but don’t home.
Use the $limits command, and then go manually trigger each endstop on your machine. You should see each endstop state change as you trigger and un-trigger the endstops. Report what you find. If any aren’t working we need to fix that first.

timonjkl · August 2, 2025, 10:27pm

Mine did this from a random surge static burst from a refrigerator or dehumidifier or posabley the beverage cooler on the same circuit happened everytime one of the compressors started( they have their own circuit now and no more problems )as the controller.

I never leave mine alone more than one fire documented here

amprops · August 4, 2025, 3:51pm

Upon running the $Limits command, the command window showed the below when the limit switches were triggered. I’m reducing the number of “blank” lines in-between limit switch triggering to save space here.

: y
: Y
: x
: X

Upon touching the probe plate to the magnetic alligator clip;

: P