Cura 3.2.23: pause at layer

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peokuk
Posts: 5
Joined: Mon Mar 12, 2018 12:00 pm

Cura 3.2.23: pause at layer

Post by peokuk » Wed Aug 01, 2018 11:00 am

Is there a trick to getting pause at layer to work with 3.2.23?

I had it working with 2.6.69, but upgraded to 3.2.21 and both broke. Uninstalled everything and tried again with 3.2.23 without luck.

I like the features of 3.2.23, but it seems like I would need a clean install of *only* 2.6.69 to get a working plugin?

And by 'broke', I mean the print head tries to move through the print bed when I resume....

b-morgan
Posts: 247
Joined: Fri Aug 11, 2017 8:53 am

Re: Cura 3.2.23: pause at layer

Post by b-morgan » Thu Aug 02, 2018 4:15 pm

Can you post the gcode for a print that exhibits this behavior?

peokuk
Posts: 5
Joined: Mon Mar 12, 2018 12:00 pm

Re: Cura 3.2.23: pause at layer

Post by peokuk » Thu Aug 02, 2018 9:37 pm

LM_Cone_40mm.gcode
pause at layer... 6?
(1.55 MiB) Downloaded 71 times
Here you go, thanks! Lulzbot Mini (1), btw.

b-morgan
Posts: 247
Joined: Fri Aug 11, 2017 8:53 am

Re: Cura 3.2.23: pause at layer

Post by b-morgan » Fri Aug 03, 2018 11:28 am

The gcode inserted by PauseAtHeightorLayer.py appears to be correct.

When the code is executed, the printer should raise Z by 1mm, move to (default) X,Y 190,190 and then (because current Z is less than 15) raise Z to 15mm to allow some room under the nozzle. When the pause is resumed (under the assumption that the toolhead has not moved, only filament adjustment), 50mm of filament is extruded, a (default) 5 second pause for the operator to wipe the nozzle, Z is lowered to the original Z plus 1mm, and X,Y and the value for E are restored to their original location / values. The first command from the original gcode should lower Z by the 1 mm added by the pause code and the print continues from there.

If the nozzle is being driven into the bed, one possibility is that the assumption that the toolhead was not moved while the printer was paused is wrong.

I guess another possibility is that the pause time was so long that the firmware timed out and lost track of the Z position.

My last guess (which may be my best guess), X190 Y190 is outside of the dimensions for a Mini. The script allows for those values to be input, 190 is the default. Perhaps a default of X0 Y0 would have been a better choice as that location should be valid for all (Lulzbot) printers.

Can you provide any additional input that would narrow down the actual cause of the error?

JoeBowler300
Posts: 75
Joined: Thu Apr 28, 2016 12:20 am

Re: Cura 3.2.23: pause at layer

Post by JoeBowler300 » Fri Aug 03, 2018 11:10 pm

Where is this plugin? How do I get it? How do I toggle it?
I'm using Cura LE 3.2.23
Installed and Browse Plugins doesn't show a "Pause at Height" plugin

kmanley57
Posts: 1109
Joined: Sun Feb 01, 2015 3:53 pm

Re: Cura 3.2.23: pause at layer

Post by kmanley57 » Sat Aug 04, 2018 5:28 am

Look here:

Extensions
Post Processing
Modify-code


Then you will find it under Add a script on the window that pops up.
I will express my CRAZY ideas at any time! So you have been warned. None of my opinions are Lulzbots and can be wrong at any second.

JoeBowler300
Posts: 75
Joined: Thu Apr 28, 2016 12:20 am

Re: Cura 3.2.23: pause at layer

Post by JoeBowler300 » Sat Aug 04, 2018 10:41 am

Thank you!

peokuk
Posts: 5
Joined: Mon Mar 12, 2018 12:00 pm

Re: Cura 3.2.23: pause at layer

Post by peokuk » Tue Aug 07, 2018 10:21 pm

@b-morgan,
that helped! I went with your last guess and set it to X0 Y0 and it worked fine... for the first layer.

After that it would extrude a big blob and then retract as fast as I've ever seen it go, stripping out the filament. Next layer it didn't extrude the blob, but did retract again and strip the filament.

Are there assumptions or corrections the firmware will do that would cause the extrude/retract behavior?
Attachments
LM_Cone_40mm.gcode
5 pauses
(2.76 MiB) Downloaded 26 times

b-morgan
Posts: 247
Joined: Fri Aug 11, 2017 8:53 am

Re: Cura 3.2.23: pause at layer

Post by b-morgan » Mon Dec 24, 2018 5:04 pm

peokuk wrote:
Tue Aug 07, 2018 10:21 pm
@b-morgan,
that helped! I went with your last guess and set it to X0 Y0 and it worked fine... for the first layer.

After that it would extrude a big blob and then retract as fast as I've ever seen it go, stripping out the filament. Next layer it didn't extrude the blob, but did retract again and strip the filament.

Are there assumptions or corrections the firmware will do that would cause the extrude/retract behavior?
Sorry I'm a bit late with my reply!

I looked at the gcode and the second and subsequent uses of the script are generating bad code because the script seems to have forgotten that the E mode is absolute. The first instance sets E mode to relative and then sets it back to E absolute. The second and subsequent uses insert relative E commands without setting the mode to relative (and all hell breaks loose).

I'll see if I can figure out what's wrong and post a revised version of the script when I do.

b-morgan
Posts: 247
Joined: Fri Aug 11, 2017 8:53 am

Re: Cura 3.2.23: pause at layer

Post by b-morgan » Mon Dec 24, 2018 5:39 pm

I've attached an updated version of the script that fixes the second and subsequent uses of the script in a single gcode file.
Attachments
PauseAtHeightorLayer3.zip
(6.49 KiB) Downloaded 37 times

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