G29, G30, G32, M558 and dive height

Surgikill

Hi all,

I'm trying to set up variable dive heights for my printer. I have 4 independent lead screws on my corexy bed. I want to be able to run true bed leveling (G32) with a dive height of 10-15mm, in case the leadscrews are backdriven while removing a part and the bed is very far out of parallel. I also want to run mesh bed compensation (G29), to test the flatness of my bed. The issue I am running into is that mesh bed compensation is using the 10-15mm dive height that is set in M558. I have tried reducing the dive height in M558, and then adding G1 Z15 in bed.g after each probe point, but it still moves to the 3mm dive height after moving to G1 Z15. Is there a way I can get around this? It doesn't look like there are any variables in G29 or G30 that I could assign for custom dive heights, and I don't see a file for mesh compensation that G29 calls out too. Would my best bet be to create a macro for mesh bed leveling and append a modified M558 to the beginning of the macro?

Thanks.

Surgikill

It also seems that if I try to make a macro for mesh bed compensation, it throws everything off.

G28			; home printer
M400			; wait for buffer to clear
M558 K0 P8 C"^121.io0.in" H2 F300:120 T12000 A3 S0.02      
                                 ; K0 for probe 0, P5 for NC switch, C for input pin, 
                                 ; ^ for enabling the native pullup resistor on Duet 2 
                                 ; hardware running RRF3  
                                 ; H dive height of 2mm, F300 probing speed 5mm/sec, 
                                 ; T9000 travel speed 150mm/sec,   
                                  ; A3 number of probes 1, S0.01 max tolerance of 0.01
																
G1 Z15			; Move to Z=15
G29			; Run mesh compensation

M558 K0 P8 C"^121.io0.in" H10 F300:120 T12000 A3 S0.02      	
                                                                ; Resest z probe properties
                                                                ; K0 for probe 0, P5 for NC switch, C for input pin, 
                                                                ; ^ for enabling the native pullup resistor on Duet 2 
                                                                ; hardware running RRF3  
                                                                ; H dive height of 8mm, F300 probing speed 5mm/sec, 
                                                                ; T9000 travel speed 150mm/sec,   
                                                                ; A3 number of probes 1, S0.01 max tolerance of 0.01

If I run this, the printer moves to the first mesh point, but does NOT include the xy offset of the z probe, and it also moves to about 2mm below the nozzle, the dive height that is set in the M558. Do I also need to include G31 after re-running M558?

Phaedrux

@Surgikill said in G29, G30, G32, M558 and dive height:

If I run this, the printer moves to the first mesh point, but does NOT include the xy offset of the z probe,

The issue is that you're including a full M558 command including the probe type. When you do that, the G31 is reset, so you need to either simplify your M558 command to only modify the parameters needed and leave the full basic command in config.g, or include a G31 command after the M558 K0 P8 ....etc

Surgikill

@Phaedrux thanks, I'm going to try that when I get home.

Surgikill

@Phaedrux Added M558 with just the H parameter to my G29 macro and now it works perfectly. Thank you.