[SZP] Scanning Z probes as regular Z probes

cdillow

I see as of 3.5.0-rc.3 a Scanning Z probe can be used as a Z-Stop? I am a bit confused as to how to do that.
I got it so somewhat work by touching the head to the bed and doing a G91 Z0 and then M558.1 K1 S2 to calibrate but I am sure I am missing something on how to correctly use it. Surely you don't have to set the Z0 reference to calibrate do you?

I have this in my config.g
; Scanning Z probe
M558 K1 P11 C"121.i2c.ldc1612" F36000 T36000
M308 A"SZP coil" S10 Y"thermistor" P"121.temp2" ; thermistor on coil
M558.2 K1 S13 R148466
G31 K1 X10 Y10 Z3 ; set Z probe trigger value, offset and trigger height - Smaller number further away from the bed
M557 X50:240 Y50:240 S10

And this in homeall.g
M558 P11 F1000500
G30 K1

cdillow

I got a little further by adding a Pnnn Trigger value to G31. But I get a Probe trigger before move error but the trigger value is well below the trigger point. I also realize you should use temp compensation but just trying to get it work first. Does anyone have any examples of using Scanning Z probes as regular Z probe?

Phaedrux

@cdillow said in [SZP] Scanning Z probes as regular Z probes:

And this in homeall.g
M558 P11 F1000500

Don't include P if you intend to only change he speed. (Which seems insane by the way). You'd also need to include the K1.

cdillow

@Phaedrux said in [SZP] Scanning Z probes as regular Z probes:

@cdillow said in [SZP] Scanning Z probes as regular Z probes:

And this in homeall.g
M558 P11 F1000500

Don't include P if you intend to only change he speed. (Which seems insane by the way). You'd also need to include the K1.

Ah sorry the cut and paste dropped my :

That should have been

M558 K1 F1000:100:500

Phaedrux

You can put your gcode into a code block so that the forum doesn't eat your characters. Use the little </> button.

cdillow

@Phaedrux Thanks should have known using escape chars..

Phaedrux

Yes that looks ok, and if you only have a single probe you don't need to use the K parameter at all. If you do use it, make sure you use it everywhere that references the probe in question.

cdillow

@Phaedrux Well the default for K is 0 and this Scanning Coil Probe is K1 and not sure that can be changed.

Phaedrux

How many probes do you have?

cdillow

@Phaedrux Only 1 so why am I defining it as K1. Duh.

robotsneversleep

Hi @cdillow, how well is using the Scanning Z probe as the only probe working out for you? I'm considering doing the same, but as you pointed out, there doesn't seem to be much guidance on exactly how to go about doing this properly.

Have you found that your Z probe trigger height is consistent, or does it change with temperature, in which case you need T compensation?
If you have done some temperature compensation, how did you do it?

Just thinking out loud here, but my hope is that I only need to find Z=0 once (or Z=0 for each bed surface I use) and the M558.1 calibration will do the rest.

WOPR73

@cdillow @Phaedrux @dc42 I am trying configure my SZP and I hate to ask this... But, does there need to be a K0 and a K1 to do a complete probe of the bed? K0 for the initial Z height probe, then K1 will does the scanning of the complete bed? So I would need a blt or pinda probe plus the SZP???

cdillow

@WOPR73 You can just configure the SZP to be the first and only Z probe or K0 and do both initial and scanning operations. I got that to work but once in a while the printer would crash into the bed when doing the initial probe. Then I changed by bed from G10 to and PEI coated spring steel plate and then found I could not get the SZP calibrated to work as a initial Z0 finding probe at all. I broke down and installed a BLTouch to find Z0 as K0 and then the SZP as a scanning probe as K1.

WOPR73

@cdillow Yeah, that's I what I though. You are not the only one that has made that change. I did not find anyone that has the SZP working as the only Z probe. Almost all use the BLT and SZP together. With having to add another probe to the hotends weight, plus I have to add the Duet3D Filament Monitor to the Duet 3 1LC tool board in order to make that work... I am now adding even more weight. I thought with using the 1LC it would clean up the rats nest at the hotend. I really like the RRF and the Duet 3 6HC mainboard... I just spent to much time and money to get this all in one Duet setup to work and it's making things more complicated and heavy then all other hotend designs. I guess BTT and Klipper it is...

Thanks for your help and good luck!

Polyneutron21

The SZP show up in the Duet Web control, and communication looks great, the problem is with M308 is says S10 is not a valid sensor pin.

Phaedrux

@Polyneutron21 said in [SZP] Scanning Z probes as regular Z probes:

The SZP show up in the Duet Web control, and communication looks great, the problem is with M308 is says S10 is not a valid sensor pin.

I think you should start a new thread and provide some additional information about your setup.