Duet Wifi and BLTouch

ozi

I Used the same wiring for pi and duet but pi worked.

However it was a wiring issue so I made a new one and now it works. Its strange that the same old wire worked with the pi but not with the duet.. I dont know why but i am happy it works

ozi

But now I am trying something else:

I have 2 seperate z axis steppers on my hypercube rs. I already tryed with the following link https://duet3d.dozuki.com/Wiki/Bed_levelling_using_multiple_independent_Z_motors but I think it will make some changes in my heightmap so everytime I use G32 I have to make G29 again.

Now I find the following tutorial for an Ender printer:
https://duet3d.dozuki.com/Guide/Ender+3+Pro+and+Duet+Maestro+Guide+Part+5:+Upgrades/54#s213

What I want is when I turn on the printer I would like to Home both z steppers to z max with 2 optical switches at z max to geht them balanced. And then to HomeALL to probe the center of my bed with the bltouch and then make an heightmap to load it at every print.

So now I have installed 2 optical switches to Z MAX.
1st Z motor is connected to Z1
2nd Z motor is conencted to E1

So my config.g is now:
; Drives
M569 P0 S1 ; physical drive 0 goes forwards
M569 P1 S1 ; physical drive 1 goes forwards
M569 P2 S1 ; physical drive 2 goes forwards
M569 P3 S1 ; physical drive 3 goes forwards
M569 P4 S1 ; new drive for second z
M584 X0 Y1 E3 Z2:4 U4 ; set drive mapping
M350 X16 Y16 Z16 U16 E16 I1 ; configure microstepping with interpolation
M92 X80.00 Y80.00 Z400.00 U400.00 E407.2 ; set steps per mm
M566 X800 Y800 Z12 U12 E1000 ; Set maximum instantaneous speed changes (mm/min)
M203 X10000 Y10000 Z400 U400 E10000 ; Set maximum speeds (mm/min)
M201 X500 Y500 Z250 U250 E500 ; Set accelerations (mm/s^2)
M906 X1000 Y1000 Z1000 U1000 E1000 I30 ; Set motor currents (mA) and motor idle factor in per cent
M84 S180 ; Set idle timeout

; Axis Limits
M208 X0 Y0 Z0 U0 S1 ; set axis minima
M208 X290 Y285 Z300 U300 S0 ; set axis maxima

; Endstops
M574 X1 Y1 Z2 U2 S1 ; set active high endstops

; Z-Probe
;M574 Z1 U1 S2 ; Set endstops controlled by probe
M307 H3 A-1 C-1 D-1 ; Disable heater on PWM channel for BLTouch
M558 P9 H5 F100 T2000 ; Set Z probe type to bltouch and the dive height + speeds
;G31 P25 X0 Y65 Z2.30 ; Set Z probe trigger value, offset and trigger height
G31 P25 X0 Y65 Z3.60 ; Set Z probe trigger value, offset and trigger height
M557 X20:280 Y20:280 S20 ; Define mesh grid

Note: I had to uncomment M574 to get the new 2 z entstops working

homez.g:
G91
G1 S1 Z300 U300 F600
G1 S2 Z-2 U-2 F600
G1 S1 Z10 U10 F300
G1 S2 Z-1 U-1 F300
G90
M913 X100 Y100 Z100

homeall.g:
G91 ; relative positioning
G1 H2 Z5 F6000 ; lift Z relative to current position
G1 H1 X-225 Y-225 F1800 ; move quickly to X or Y endstop and stop there (first pass)
G1 H1 X-225 ; home X axis
G1 H1 Y-225 ; home Y axis
G1 X5 Y5 F6000 ; go back a few mm
G1 H1 X-225 F360 ; move slowly to X axis endstop once more (second pass)
G1 H1 Y-225 ; then move slowly to Y axis endstop
G90 ; absolute positioning
G1 X150 Y85 F6000 ; go to first bed probe point and home Z
G30 ; home Z by probing the bed

So If I home Z (after X and Y) both Z motors are going to ZMAX until hitting the 2 endstops.
Then I do HomeAll the bed is going Up again and it makes the probe at the center with the BLtouch. But then I get an error that homeu.g could not be found.

Can someone help me to geht this worked? Or does anyone have an Idea if I can make the same thing to balance the z motors with zmin and probe with bltouch? (I already tryed this but its not working because when i would like to probe with bl touch its always hitting the endstops from z).

fcwilt

The most important function of the Z probe is to set the X=0 datum.

You generally want to do this at the center of the bed and you always use the same point.

This needs to be done...

after you level the bed with G32
before you create a height map with G29
before you load a existing height map with G29 S1

You can do it as the last step of homing Z but that is not essential.

fcwilt

Hi,

If you are not using firmware v3.1.1 or v3.2 I strongly suggest you do so.

It makes leveling the bed with multiple steppers very simple.

Frederick

ozi

So it wont work like i tried ?

I think my bed is a little bit heavy so its to easy that one of the leadscrews will turn a little bit when the printer is off. And this will make the heightmap unusable... I dont want to mesh bed levelin every day ..

what does the new firmware do different with bltouch? I will try tomorrow.

fcwilt

@ozi said in Duet Wifi and BLTouch:

So it wont work like i tried ?

I think my bed is a little bit heavy so its to easy that one of the leadscrews will turn a little bit when the printer is off. And this will make the heightmap unusable... I dont want to mesh bed levelin every day ..

what does the new firmware do different with bltouch? I will try tomorrow.

Hi,

Let's agree on some terms first.

Mesh compensation is the firmware feature that allows the firmware to adjust the Z co-ordinate during printing to compensate for bed irregularities.

While it can compensate for a bed that is not level that is not it's main focus.

Mesh compensation requires creating/loading a height map. The base command is G29.

So don't think of it as leveling the bed - that is a different firmware feature.

The firmware offers two ways to level the bed...

(the) Manual Bed Leveling Assistant (MBLA)
Automatic Bed Leveling (ABL)

They are similar but MBLA relies on turning bed leveling thumb screws by hand whereas ABL relies on adjusting multiple Z steppers to level the bed.

The base command is G32.

It looks like you have two independent Z steppers so you can use ABL.

One of the many advantages of firmware v3 is it simplifies using ABL.

I don't know of any significant differences in it's handling of a BLTouch.

I have a printer with three Z steppers and I use ABL - it works great.

I also use mesh compensation but I have found that I can use the same height map as long as I use ABL before creating the height map and before loading the height map to print.

So consider upgrading to v3 firmware and let me know.

Frederick

Phaedrux

It's much easier with RRF3.

https://duet3d.dozuki.com/Wiki/Bed_levelling_using_multiple_independent_Z_motors#Section_In_RepRapFirmware_Num_3

After leveling the bed with that technique make sure you set Z0 with the probe by using G30 at the center of the bed before you run G29 or G29 S1 and start a print. @fcwilt has you covered.

ozi

Thank you all !

I am a little bit confused and feel like an idiot ...

To explain why I am trying this with zmax is:
I used and tryed the ABL with the bltouch like explained in this tutorial with RFF2:
https://duet3d.dozuki.com/Wiki/Bed_levelling_using_multiple_independent_Z_motors#Section_In_RepRapFirmware_Num_3

I run first G32 and then G29 to create a height map. I then changed my start gcode from G28
G29 S1
to
G32
G29 S1

I thought that is ok because G32 runs bed.g and the first line of bed.g is g28. But now I see (thanks fcwilt) I had to set X=0 AFTER G32 - maybe this was my issue why I had the feeling the G32 changes my heightmap.

So today, I will upgrade to RFF3 an try it again but im confused about the tutorial now.

For RFF2 in bed.g it says :"M401 ; deploy Z probe (omit if using bltouch)" so I uncommented it and the bltouch is probing the bed to the center, then left at the near of leadscrew and right the same.

For RFF3 the tutorial is "speaking" again from "endstops" so now I am confused. (Sorry for my english :(.. ).

So is it right, I can use 2 endstop in Z MIN ! to make the ABL and the BLtoch for G28 and G29 to home the center and create a heightmap? Sorry If I am annoying..

ozi

So I have now updated to RFF3. I unplugged for the first installation the 2 z optical endstops and in the configuration tool I choosed Z-Probe as Z endstop at low and and configured the bltouch for the probe.

In config.g I made changes in M584 to get the second z motor working like:
M584 X0 Y1 Z2:4 E3

So now when I do homeall it is using the bltouch as my "z endstop" and both z motors are working.

Now as fcwilt described, its only a z probe but not ABL? I think I have now understanded it. Z Probe is not the same like Z home.

So homez calls the motor to home using endstop and G29 calls a probe definied with M558 P9 (for bltouch). I think i have it now and I dont need zmax and can use zmin.

I will try now and will report my progress

ozi

I give up..

Tryed everything what i can but it wont work use 2 endsop switches and the bltouch for probing.

I removed the jumpers and put the second z motor back from e1 to z2 again and will only use bltouch as probe and endstop.. maybe one day I will find someone who has time to explain and test it with me.

thank you all

fcwilt

@ozi said in Duet Wifi and BLTouch:

I give up..

Tryed everything what i can but it wont work use 2 endsop switches and the bltouch for probing.

I removed the jumpers and put the second z motor back from e1 to z2 again and will only use bltouch as probe and endstop.. maybe one day I will find someone who has time to explain and test it with me.

thank you all

When using end stop switches with ABL the z probe is only used AFTER to reset the Z=0 datum.

Recall that I have 3 Z steppers, each with their own end stop switch, for my bed.

Here is most of my homez.g file:

G91                  ; relative moves
G1 Z-399 F1200 H1    ; move up until endstop switch is activated
G1 Z20   F600        ; move down a bit
G1 Z-25  F300  H1    ; move up until endstop switch is activated
G92 Z10.200          ; set Z as needed to yield accurate Z = 1
G90	             ; absolute moves
G1 Z10 F1200         ; move nozzle to known position
G32                  ; invoke bed.g to level bed - pass 1
G32                  ; invoke bed.g to level bed - pass 2

Note that each Z stepper keeps moving until it's end stop switch is activated. Once all are activated the next step in the homing file takes place.

Frederick

ozi

I have tryed like your homez.g file and in config with M584 Z2:4, but had the following issue:
G91
G1 Z-305 F600 H1 -> Only the z motor connected on Z is moving the other one is not moving

Then I trigger the switch for Z and now BOTH motors going 20mm down (G1 Z20 F600) and then with G1 Z-25 F300 H1 the same only one motor is going up again.

And the same when I trigger the switch a second time BOTH motors are going down zo G90 Z10

I had M584 Z2:4 in config.g
I had M574 Z1 S1 P"zstop+e1stop"

but when z moving to Endstop (with H1) only one stepper is moving, when moving without H1 both are moving..

I dont now.. i give up

fcwilt

@ozi said in Duet Wifi and BLTouch:

G1 Z-305 F600 H1 -> Only the z motor connected on Z is moving the other one is not moving

That tells me that the end stop switch for the other stepper is already activated. Remember that with H1 the move stops when the end stop switch activates or is already activated.

Then I trigger the switch for Z and now BOTH motors going 20mm down

Triggering the switch completed the first G1 H1 move and then the G1 Z20 command was executed.

then with G1 Z-25 F300 H1 the same only one motor is going up again.

Again because the end stop switch for the other stepper is already activated.

And the same when I trigger the switch a second time BOTH motors are going down zo G90 Z10

Triggering the switch completed the second G1 H1 move and then the G1 Z20 command was executed.

Everything you see is consistent with the other end stop switch being activated at the start.

So find out why the other end stop switch is not working and your good to go.

Frederick

ozi

@fcwilt When the other switch was triggered then the red led from the optical switch should show it but it wasnt triggered.. maybe wiring issue..

I found another topic here:
https://forum.duet3d.com/topic/9684/bl-touch-and-two-endstop-switches/2

he wanted to make the same like I but no response from him if it worked...

there was a suggestion to use bed.g for leveling the bed and bltouch to probe..

I will try later more..

fcwilt

@ozi

Hi.

Homing the bed with multiple Z steppers/end stop sensors is a different issue from leveling the bed.

You can do both.

I think I mentioned that my printer has 3 Z steppers each with it's own end stop sensor.

If your end stop sensors are correctly position you can get your bed decently level.

To "fine tune" the leveling you use your Z probe and Automatic Bed Leveling (ABL - base command G32)

Can we get your homing working first?

Frederick

ozi

@fcwilt Oh my god.. I am the biggest idiot the last days here.. my god.. i feel really bad now

It was my false wiring.. i plugged the endstops to E0 and Z insted auf E1 and Z.. i am so sorry that i wasted your time. If you ever come to austria/vienna i will spend for some beer..

So now I can use homez.g and homeall.g to home both z steppers. And G29 to create a heightmap with the bltouch. I made a makro with G30 in the center of the bed to probe the center if i had do measure the z offset for the bltouch.. Soo now i am heating up my bed, will use homez.g get the z=0, then I will level manuelly with the screews and create a heightmap with bltouch to get it perfect

fcwilt

@ozi said in Duet Wifi and BLTouch:

austria/vienna i will spend for some beer..

That is weird that you should mention that.

My wife and I were chatting just day or two ago about places we would like to visit while we were still above ground.

As part of our research I used Google Earth to "visit" Vienna.

Frederick

ozi

@fcwilt vienna has a big history and a lot of sightseeing so just pm me if you ever come over