Z probe frustration

luckyflyer

I'm very frustrated with my Orion piezo having inconsistent z probes. I'm wondering what besides an automatic bed mesh do I give up by going back to a Z end stop switch? It seems like I'll be trading auto bed mesh with the pitfalls of a z probe for the simplicity of the Z end stop switch. I don't do a bed mesh calibration very often so doing a manual 12 point mesh shouldn't be very difficult. Anything else I'm missing?

fcwilt

@luckyflyer

I don't know your probe but I would not be surprised if it is the problem.

I have five printers all equipped with Z probes (2 BLTouch, 2 Inductive, 1 Euclid). They all work just fine. So I don't think the firmware is the source of your problem.

It could also just be your configuration.

What are the symptoms you are seeing?

Frederick

luckyflyer

@fcwilt
The printer is laying down the filament inconsistently. For example on print #1 the nozzle is too close to the bed squeezing the filament causing the nozzle to plow the first layer (petg). I abort and possibly on the next try the nozzle will be too far from the bed causing adhesion problems. Rarely do I get the ideal first layer. With pla I could tweak using the micro step up/dn on the panel due. Here are some z probe repeatability tests I ran a few minutes ago.
1/6/2022, 9:29:00 PM M98 P"0:/macros/Z probe repeatability.txt"
Error: Z probe readings not consistent

G32 bed probe heights: 0.008 0.006 0.000 0.014 -0.005 0.013 0.019 0.019 0.006 0.010, mean 0.009, deviation from mean 0.007
1/6/2022, 9:27:38 PM M98 P"0:/macros/Z probe repeatability.txt"
Error: Z probe readings not consistent
Error: Z probe readings not consistent
G32 bed probe heights: 0.024 0.005 -0.049 -0.002 -0.070 0.001 -0.064 0.005 -0.044 -0.010, mean -0.020, deviation from mean 0.031
1/6/2022, 9:25:40 PM M98 P"0:/macros/Z probe repeatability.txt"
Error: Z probe readings not consistent
G32 bed probe heights: -0.155 -0.096 -0.170 -0.190 -0.192 -0.218 -0.106 -0.114 -0.116 -0.112, mean -0.147, deviation from mean 0.041

I'm just pondering how to go forward, Thanks

fcwilt

@luckyflyer

Well since the probe appears to be basically working I would think your configuration is good.

But the readings are varying a lot.

If that happened to me I would suspect the probe OR perhaps the mounting of the probe.

Frederick

MikeDC

@luckyflyer
you didnt mention what firmware you are on or the configuration of your motors or boards.

there are 2 things come to my mind that cause this .

later beta firmwares a bug if your Z motors are on an expansion board,
if not on the later beta firmwares then check your wiring, if the probe wire is unshielded and running close to heater or motor wires then it could be picking up EMI type interference. on a bltouch or opto sensor this can be easier to see, the can led flicker on either of these and sometimes on bltouch type sensors the probe may start to drop.

engikeneer

@luckyflyer show us your config and maybe a picture of your print head. I had mixed results with my Orion depending on how I had it mounted.
Originally I had my V6 mounted using the provided mounts on quite a stiff x gantry and I got pretty good results.
I then switched to a Chimera so had to design my own mount. First few iterations I didn't get it right and had big problems with repeatability. I found designing the mount to have stiffness in the right places and flex in others wasnt very straightforward. I also had some issues that the print head was cantilevered off the gantry. This meant that the gantry wasn't very torsionally stiff so the nozzle would be pushed upwards when it hit the bed, reducing my accuracy.
After a few iterations I got it working okay, but eventually switch over to a bltouch as mounting the Orion, chimera and two extruders in the print head was quite heavy and cumbersome.

Are you probing hot or cold? I found I had best result probing with a nozzle at 130C. Hot enough for it to squish any filament drooling from the nozzle, but not hot enough to damage my bed or cause additional drool. J then always did a double probe. One dummy probe to squish any drool 10mm off from my actual probe point, before doing the actual probe.

You can also use the A and S parameters in M558 to make it do repeated probes at each point and take an average. I found this helped a lot in giving more consistent results (though takes a little longer at the start of each print)