CNC Error During Probe Z - Error Fixed / Probe Red Tagged

@dannym @JoeN - Immediate Assistance Requested

Hey Everyone,

This morning I came in to run the CNC. When I “Probe Zed” the machine it did not double tap the probe as it normally does and continued to plunge until I hit the E-stop. The probe is currently trapped between the material. Safe Z does not work due to having hit the E-stop. I will have pictures shortly and will be contacting everyone on the skedda list today for the CNC.

now that you hit estop. You can rotate the screw that controls the z height by hand and get the probe out

1 Like

Thank you to @JoeN for the quick assistance. Everything is good to go now however the paper method should be used to zero the Z until someone takes a look at the probe.

The same thing happened to me last week. There are two z probes in the drawers. One is programed and works, the other is not programed and will cause what you’ve described. The probe that works has two small holes punched in the metal disc.

We should probably put the spare in a stewards cabinet to prevent this from continuing to happen to people.

1 Like

Or at least label it. I have been guilty of knowing my intentions and not informing other members about it.

The one I used was the one with two small holes. It normally works fine and it still does have battery. Joe mentioned it could be a spring. I’ve tagged it, put a note on it and left it near the computers until someone can take a look at it. If there’s anything else that should be done let me know. I’ll be here for another hour and a half or so.

Weird. I used it last night around 8pm and it was working fine.

If you walk up to your appointed time and the router driver power is on. Go ahead and restart the whole system. It helps clear any errors.

The existing probe with a couple of holes has been working, one LED was punched out with a third hole that tactically went straight through it. It’s still there, just below the surface.

Did you check that the LEDs indicate it’s working and lights up before probing? Dead batteries are common.

The new one has been around for awhile. Although a newer build from the same mfg, the aluminum plunger switch was too tight in the sleeve of the molded plastic body, it wanted to bind and read as touched. It’s glued together so we can’t take it apart to sand the sleeve interior. I did try a bunch of stuff including heating the aluminum and working it back and forth. Got better but was still pretty bind-y but it could have gotten better with time.

The transmitter and receiver are hardcoded to only talk with their corresponding device. So using the other probe does mean the receiver must be swapped out too.

Yeah, it is strange. The probe has battery and the lights were on before using it.

I spoke with the guys that were scheduled after me, they ran last night too and had no issues. They are currently running the CNC and used the paper method for zeroing.

Well, for additional testing, you don’t have to place the sensor under the bit where a fault would cause a damaging crash if it doesn’t respond. You can just hold the probe in your hand as you press Probe Z, and click the probe to see the Z axis stop, retract, and slow-probe and click again and it should set the Z=0 there and do a rapid retract and stop.

1 Like

From estop, after you rotate the red mushroom button to pop it back up, LinuxCNC will be in the “unpowered” state. However, this is not configured to actually depower the drives, since freewheeling is less desirable. You can’t manually turn the leadscrew unless the box is turned off via the 120V power strip switch.

Hit “toggle machine power” on the terminal and the arrow keys and jog wheel can be used to move the Z off the switch. “Safe Z” won’t work, or at least shouldn’t be used, since the Z axis was in motion at the time of e-stop it will be dehomed and the system is not aware of the machine coordinates on the Z axis, so it will not know what the Safe Z height is.

1 Like

FYI the batteries in the probe were freshly replaced on Sunday afternoon. (It worked at that point)

When the cnc is on for a long time. There are random errors that can occur. I recommend restarting the desktop and driver power when you start your cut time.

I use wincnc on my router and I have weirdness that happens from time to time when I have the cnc powered up for a long time.