Solved: Setting Z offset for T1

[T3P3Tony]

If you do a tool change what happens to the z height of the bed/z axis?

[RajaaKahel]

@t3p3tony During a tool change I see the Z moves a bit from the nozzle by about 0.4mm or something.

[T3P3Tony]

@rajaakahel are you sure it's not moving 0.85mm as you have configured?

[RajaaKahel]

@t3p3tony Yes I'm sure, check the picture, now I tried again with 50mm Z offset for T1, but nothing happens..

[RajaaKahel]

@t3p3tony Now during the last test:
"I tried again with 50mm Z offset for T1"
Something very strange happened!
First T0 was printing, then the tool changed to T1 (nothing happened, no Z offset) but then when the tool changed back to T0 the bed moved by about 50mm down and went back to continue printing.
After that and before that it didn't move down by 50mm at all.

[zerspaner_gerd]

@RajaaKahel

After the tool change, a Z value must be present, otherwise the axis will not be approached.

Part of my tool change script from S3D:

T[new_tool] ; New Tool

G1 X[next_position_x] Y[next_position_y] Z[next_position_z] F9000

[RajaaKahel]

@zerspaner_gerd My problem is that Duet is not applying the offset I want for T1. It's ignoring it. Through G10 in config.g and through any other command anywhere else.
Also it's acting weird if you read my last comment.

[zerspaner_gerd]

@rajaakahel For me, the z-offset works, why should not it work for you?

Share your gcode, maybe I can find an explanation!

Which firmware version do you use?

[RajaaKahel]

@zerspaner_gerd 0_1535130513803_8.gcode

Macros:
https://drive.google.com/open?id=1Nwte-EtKEzL_ogCqJp7PMQ2qsLK7RBkM

Configurations:
https://drive.google.com/open?id=1q-h8eojJ91CQwK2p5YhWKuQaQph0sQ_T

Here's everything.. I'd appreciate it if you or anyone could find anything!

[zerspaner_gerd]

I have to give up, Sorry.

I find no big differences to my config.g.
The gcode is already very different but he should not make these problems!

Maybe a try, copy your tool Macro directly into the Duet Tool Macro, so that without M98 (subbrogram)

[dc42]

@RajaaKahel, if the tool 1 nozzle is 0.85mm lower than tool 0 then I think you need Z-0.85 in the G10 P1 command, not Z0.85.

[RajaaKahel]

@dc42 Tool 1 nozzle is actually longer than Tool 0 nozzle by 0.85mm.
I updated to:
Firmware Version: 2.02beta1(RTOS) (2018-08-12b5)
WiFi Server Version: 1.21RC4(08b3)
Web Interface Version: 1.22

Nothing solved.

[dc42]

@rajaakahel said in Setting Z offset for T1:

@dc42 Tool 1 nozzle is actually longer than Tool 0 nozzle by 0.85mm.

So do you mean the Tool 1 nozzle is 0.85mm lower than tool 0, or higher?

Where two tools have different nozzle heights, in the tool change files (probably the tpre file) you will need to raise Z so that when you bring in the tool with the lower nozzle after using the other one, its nozzle will be clear of the print. Use command G1 R2 Z0 at or near the end of the tpost file to put it at the right height before continuing the print.

[RajaaKahel]

@dc42 during the last test:
"I tried again with 50mm Z offset for T1"
Something very strange happened!
First T0 was printing, then the tool changed to T1 (nothing happened, no Z offset) but then when the tool changed back to T0 the bed moved by about 50mm down and went back to continue printing.
After that and before that it didn't move down by 50mm at all.

[RajaaKahel]

@dc42 T1 is higher than T0. I tried with many gcommands to raise the bed, but they didn't work. I'll try now with G1 R2 Z50

[RajaaKahel]

@dc42
Ok now the bed is moving down by the value I entered (50mm) Before T1 is activated but it goes back to 0.2mm (the layer height) after T1 is activated. It should go to 50.2mm after T1 is selected and stay there to print. (So now the Z offset is taken into account only during tool change).

Thank you for your time, we are getting closer

; tfree1.g
; called when tool 1 is freed
G1 R2 Z-50
M98 P/macros/parkT1

; tpre1.g
; called before tool 1 is selected

G1 R2 Z50

[RajaaKahel]

I gave up on this. So much time for nothing. Sometimes it works, sometimes it's not. even tho same commands are used and after rebooting and homing. And the most important is in config.g
The z offset doesn't work. (G10 P1 X0 Y0 Z0.85)

I'll have to redesign the tool mounts to be adjustable mechanically instead or move back to Marlin..

[dc42]

I'll look into this when I get time. However, E3D uses Duets to control their tool changers and they haven't reported any similar problems.

[RajaaKahel]

I appreciate that!

[RajaaKahel]

@dc42
Here's a short video I recorded for you so you can see what actually is happening and maybe it makes it easier to solve the problem.
I don't have any offset commands set anywhere else other than what you see in config.g.
https://www.youtube.com/watch?v=MuGbiBkKNUI