BLTouch Probe Won't Deploy

Charlie

@joergs5 said in BLTouch Probe Won't Deploy:

maybe your BLtouch is too near to the bed, please check

The print head is currently sitting around 200mm from the build plate (to prevent crashing).

BLTouch Body currently sits around 7.6mm from the bed (with the nozzle touching the bed). The pin in its retracted position sits around 2.1mm from the bed (with the nozzle touching the bed).

Phaedrux

@charlie said in BLTouch Probe Won't Deploy:

@phaedrux said in BLTouch Probe Won't Deploy:

Does M401 and M402 work to deploy or retract the probe?

Yes, it does.

In this case, I think the issue is the K0. If you're going to use K0 in your config you're going to have to use it consistently. Your homing file doesn't specify the probe number when you use G30.

@charlie said in BLTouch Probe Won't Deploy:

M558 F600 H2 A1 ; Set Z probe. Feed rate: 600 mm/min. Dive height: 2 mm. Times to probe: 1.
G30 ; Z probe quickly (1 of 2 passes).
M558 F120 H5 A1 ; Set Z probe. Feed rate: 120 mm/min. Dive height: 5 mm. Times to probe: 1.
G30 ; Home Z by probing the bed slowly (2 of 2 passes).

The G30 and M558 here must have K0 specified if you're going to use that.

https://duet3d.dozuki.com/Wiki/G30

Either remove all instances of K0 from your config and leave the deployprobe.g and retractprobe.g named as such, or convert entirely to using the number probe format. Meaning use retractprobe0.g etc and when using any M558/G30/G31 command elsewhere you must also specify K0.

I think since you only have a single probe it would be best to jsut remove all instances of K0.

Charlie

@phaedrux said in BLTouch Probe Won't Deploy:

In this case, I think the issue is the K0. If you're going to use K0 in your config you're going to have to use it consistently. Your homing file doesn't specify the probe number when you use G30.

Okay, that makes total sense. I removed all instances of K0 (in config.g, M558 and G31), but the issue persists.

fcwilt

@charlie

If you have one probe you can leave the K parameter off everywhere. It defaults to 0 in anycase.

My BLTouch connected to a Duet 2 Wifi works fine and I have no K parameters anywhere.

I'm still baffled by your problem. I also still believe we are overlooking something simple.

Frederick

Phaedrux

Are you sure you've removed all cases of K0?

Can you try this?

Power cycle your printer
Before doing anything else, send M401 and M402 to test that the pin deploys and retracts.
If that works, send G30 by itself. Does the pin deploy? Does it give an error? Does the Z axis move?

Charlie

@phaedrux said in BLTouch Probe Won't Deploy:

Are you sure you've removed all cases of K0?

Here is the new Z Probe section of the config.g

; Z Probe

M558 P9 F120 H8 R0 T6000 A1 B0 C"0.io4.in"  ; Set Z probe type.
                                               ; K (Z probe number): 0 (1).
                                               ; P (Z Probe type): 9 (BLTouch probe).
                                               ; F (Feed rate. Probing speed [mm/min]): 120.
                                               ; H (Dive height [mm]): 3.
                                               ; R (Recovery time [seconds]): 0.
                                               ; T (Travel speed [mm/min]): 6,000.
                                               ; A (Max number of times to probe each point): 1.
                                               ; B (Heaters): 0 (Leave all heaters on while probing).
                                               ; C (Endstop input): 0. (Mainboard) io4.in.

M950 S0 C"0.io4.out"                           ; Create GPIO/servo pin.
                                               ; S (Output/servo pin number): 0.
                                               ; C (Pin name): 0. (Mainboard) io4.out.

G31 P500 X0 Y22.0 Z3.105                    ; Set Z probe.
                                               ; P (Trigger value): 500.
                                               ; X (Probe X offset [mm]): 0.
                                               ; Y (Probe Y offset [mm]): 22.000.
                                               ; Z (Probe Z offset [mm]): 3.105 (This is modified for Z probe calibration. A higher offset number moves the nozzle closer to the bed.).
                                               ; K (Z probe number): 0.

M557 X25:325 Y25:313.5 P3                      ; Define Z probe mesh grid (This is the probe point grid, not the nozzle grid).
                                               ; X (Min:Max X coordinates to probe [mm]): 35 (Min) : 325 (Max).
                                               ; Y (Min:Max Y coordinates to probe [mm]): 25 (Min) : 313.5 (Max).
                                               ; P (Points to probe in each direction): 3.

homez.g

; Voron.
; 0:/sys/homez.g
; Called to home the Z axis via G28 Z.
; 2020/10/24/20:02

G91                   ; Set axes (not extruders) to relative positioning mode.
G1 H2 Z5 F6000        ; Lift Z relative to current position.
G90                   ; Set axes (not extruders) to absolute positioning mode.
G1 X175 Y151.5 F6000  ; Move X and Y axes so the Z probe is at the center of the bed.
M558 F600 H2 A1       ; Set Z probe. Feed rate: 600 mm/min. Dive height: 2 mm. Times to probe: 1.
G30                   ; Z probe quickly (1 of 2 passes).
M558 F120 H5 A1       ; Set Z probe. Feed rate: 120 mm/min. Dive height: 5 mm. Times to probe: 1.
G30                   ; Home Z by probing the bed slowly (2 of 2 passes).

and I no longer have the "0" on the deployprobe and retractprobe file names.

@phaedrux said in BLTouch Probe Won't Deploy:

Does the pin deploy? Does it give an error? Does the Z axis move?

Pin does deploy and retract with M401 and M402 respectively.

When calling G30. I get this error.

g30
Error: G30: Insufficient axes homed for bed probing

fcwilt

@charlie said in BLTouch Probe Won't Deploy:

When calling G30. I get this error.
g30
Error: G30: Insufficient axes homed for bed probing

X and Y have to be homed - are they?

Frederick

Charlie

@phaedrux said in BLTouch Probe Won't Deploy:

If that works, send G30 by itself. Does the pin deploy? Does it give an error? Does the Z axis move?

So, after getting this error:

g30
Error: G30: Insufficient axes homed for bed probing

I threw G92 X0, and then G92 Y0 in the console.

The probe did deploy in this instance.

Charlie

@fcwilt
Yes, homed X and Y after getting that error. The probe did deploy in this case.

fcwilt

@charlie

So it seems all is working and it's just a question of you being sure that X and Y are homed before trying to use the probe.

That is one of the reasons I include a Z axis endstop sensor on all my printers so I can home Z without having to worry about homing X and Y first.

Frederick

Charlie

@fcwilt said in BLTouch Probe Won't Deploy:

So it seems all is working and it's just a question of you being sure that X and Y are homed before trying to use the probe.
That is one of the reasons I include a Z axis endstop sensor on all my printers so I can home Z without having to worry about homing X and Y first.

The problem is that the probe isnt deploying when I am actually calling a homez.g or homeall.g. It is only deploying when I am following the exact workflow that @Phaedrux outlines here.
@Phaedrux

Power cycle your printer
Before doing anything else, send M401 and M402 to test that the pin deploys and retracts.
If that works, send G30 by itself. Does the pin deploy? Does it give an error? Does the Z axis move?

Phaedrux

@charlie said in BLTouch Probe Won't Deploy:

M558 F600 H2 A1 ; Set Z probe. Feed rate: 600 mm/min. Dive height: 2 mm. Times to probe: 1.

I wonder if it has something to do with your homeall setting the dive height to be less than the trigger height.

@charlie said in BLTouch Probe Won't Deploy:

G31 P500 X0 Y22.0 Z3.105

I also thought that G30 would work regardless of X and Y being homed since it should only trigger movement in Z.

Phaedrux

The only other thing I can recommend for troubleshooting is to generate a basic config using the online tool and only customizing it manually to account for the basics and seeing if it works as expected.

Are you using toolboards or expansion boards or just the 6HC?

Charlie

@phaedrux said in BLTouch Probe Won't Deploy:

I wonder if it has something to do with your homeall setting the dive height to be less than the trigger height.

In this instance of attempting to home, I am using the "Home Z" button on the DWC. Here is my most current homez.g file.

; Voron.
; 0:/sys/homez.g
; Called to home the Z axis via G28 Z.
; 2020/10/24/20:02

G91                   ; Set axes (not extruders) to relative positioning mode.
G1 H2 Z5 F6000        ; Lift Z relative to current position.
G90                   ; Set axes (not extruders) to absolute positioning mode.
G1 X175 Y151.5 F6000  ; Move X and Y axes so the Z probe is at the center of the bed.
M558 F600 H2 A1       ; Set Z probe. Feed rate: 600 mm/min. Dive height: 2 mm. Times to probe: 1.
G30                   ; Z probe quickly (1 of 2 passes).
M558 F120 H5 A1       ; Set Z probe. Feed rate: 120 mm/min. Dive height: 5 mm. Times to probe: 1.
G30                   ; Home Z by probing the bed slowly (2 of 2 passes).

Phaedrux

M558 F600 H2 A1

This sets your dive height to 2mm, but your probe trigger height is over 3mm.

Do you see how that could be an issue?

Charlie

@phaedrux said in BLTouch Probe Won't Deploy:

This sets your dive height to 2mm, but your probe trigger height is over 3mm.
Do you see how that could be an issue?

Yes, I definitely see how that can be an issue. With that said, I set that value to 8mm and the issue persists.

Charlie

@phaedrux said in BLTouch Probe Won't Deploy:

Are you using toolboards or expansion boards or just the 6HC?

I am using 6HC and an expansion board.

Do you need to be in G91 to run a G30? If I send a G90, then G30, I have the probing issue. If I send G91, then G30, it seems to probe. Is this my issue?

fcwilt

@charlie said in BLTouch Probe Won't Deploy:

@phaedrux said in BLTouch Probe Won't Deploy:

This sets your dive height to 2mm, but your probe trigger height is over 3mm.
Do you see how that could be an issue?

Yes, I definitely see how that can be an issue. With that said, I set that value to 8mm and the issue persists.

In you homing files where you are using G30 you are invoking G30 twice.

Now this is not related to your problem but you don't really need to do it twice.

So, as a test, change the code so you only do it once and be sure the dive height is large enough.

As a reference my dive height setting is 5 and the Z trigger height setting is 1.8. and I always start probing at Z=10.

Frederick

fcwilt

@charlie said in BLTouch Probe Won't Deploy:

Do you need to be in G91 to run a G30? If I send a G90, then G30, I have the probing issue. If I send G91, then G30, it seems to probe. Is this my issue?

I double checked my code to be sure and it is always put into G90 mode before do the G30.

Frederick

JoergS5

@charlie said in BLTouch Probe Won't Deploy:

The code is in GCodes3.cpp DeployZProbe() and RetractZProbe(), and looks ok.

Im not sure what this means. Please let me know if you would like to provide more information.

This was analysis of the firmware source code. It accepts 0 in the deploy/retract files and also K0. It was only a check, you don't need to do anything.

About your problem, I am currently thinking about whether moving -3 away from the endstop is maybe too low and not reset to no-contact or contact (I don't know your endstop), so the endstop may not trigger at the next slow move, which is G1 H1 and doesn't set the endstop triggered then.

E. g. such a type:

approached with high speed, 3 mm back may be too low.