Pause at height. UM2+ Connect resumes immediately after pause

[LordTakeshiXVII 1]

3D-Printer: Ultimaker 2+ Connect

Firmware Version: 1.5

Cura Version: 4.10

 

TLDR: Does Ultimaker 2+ Connect (Firmware 1.5 / Cura 4.10) support the g-code M0? Pause at height does not pause. 

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I added the "Pause at height" post processing script with the following settings.

With the method Marlin the printer correctly moves the print head to the configured coordinates, moves the build plate down and retracts the material BUT will immediately resume the printing process, meaning build plate goes up again, the print head moves to the last location and it continues to print. 

The pause is not happening. 

 

With the method griffin (default setting when opening the dialog the first time) you couldn't even tell if the script was doing anything since no movement commands are executed. The print simply continued without any interruptions since the pause command is the only thing that would have had an effect. 

 

After several hours of troubleshooting I didn't find an answer to this. 

 

I tried about 20 prints with different settings and methods. None of them where pausing the print. 

 

The machine settings for my printer are looking like this. 

Since I'm not familiar with g-code I at least tried to understand the g-code pause command M0. As far as I understood both flavors griffin and marlin use the M0 code to pause the print. 

During the troubleshooting I saw some posts/comments concerning Pause at height and Ultimaker printers that said to use Marlin for the pause at height method. Therefore I also changed the G-code flavor in the machine settings to marlin. With this setting the print didn't even start so I reverted back to griffin. 

 

When slicing the print with marlin and griffin methods both of them had the M0 command in the file. (attached are both g-code-files). 

 

Snippet from marlin g-code-file

 

Snippet from griffin g-code-file

 

In addition M300 and M117 also didn't seem to have any effect. I didn't hear a beep and the display on the printer also didn't change. I'm just mentioning it because I don't know if these issues are connected. These commands are not important to me, therefore I'm only focusing on the pause issue 🙂 

 

I mainly print via digital factory cloud directly from Cura. To be sure I also saved the files to an USB flash drive where I was sure that the g-code commands are in the files. Same result - Printer didn't pause. 

 

Do you have any advice or hint what I'm doing wrong? Is the pause command even supported by UM2+ Connect? 

 

Thank you for taking the time to read my post. Have a great day! 

UM2C_PauseAtHeightTest_grifin.gcode UM2C_PauseAtHeightTest_marlin.gcode

[gr5 2,099]

@Smithy - does UM2+C have pause feature?

 

I think UM3, S3, S5 all have it but not sure about UM2+C.

[Smithy 1,141]

The UM2+C has the feature to manually pause a print via the printers menu, so it should also be possible to do it via gcode, because as far as I know the menu feature does exactly the same and sends an command. Manually it works, I just tested it.

 

But I can remember there was a problem with pause at layer, this was not working for me when I tried it some years ago, but pause at layer height in mm worked. So please also try it with height instead of the layer number.

[LordTakeshiXVII 1]

Thank you for your replies! 

 

I just tested some scenarios with pause at height in mm. 

Unfortunately I have the same issue. The generated g-code is also basically the same with M0 for the pause command. 

 

Manually pausing works fine for me as well. 

 

It would be very interesting to know what g-code is send from the pause function of the printer itself, so I can try to replace the generated g-code pause command. I contacted Ultimaker Support directly and asked for this information. 

 

I'll let you know if I can resolve the issue. 

[Smithy 1,141]

9 hours ago, LordTakeshiXVII said:

I'll let you know if I can resolve the issue. 

Thanks a lot!

[GregValiant 1,145]

I thought I'd throw this in as it might have some relevance.

Last summer Creality switched to a 32bit mainboard for their printers and they immediately developed (what sounds like) this problem.  After much time chasing it around - it appears (for the Creality machines) that the new style TFT LCD screens weren't enabled in the firmware.  As a consequence M0, M1, and M117 didn't work because the printer couldn't interpret the messages to the screen and so the printer ignored the command and as a consequence, Pause at Height doesn't work on those machines unless the firmware is changed.

 

A workaround is to insert "G4 Sxxxx" in the "gcode after pause" box.  That will Dwell the printer for "S" number of seconds.  One downside is that you have to be standing there watching the machine because unlike a pause that must be manually restarted, a Dwell is a timed event.  When the time runs down the printer takes off.  Another issue is that there is a hard limit of 1800seconds for the Disarm Timeout coded into the plugin.  Your dwell must be less than the disarm timeout or the steppers will lose location.  Finally, there is no way to re-start the machine during a dwell.  You have to wait the full dwell time.

 

But wait...there's more.  If you have Z-Hops enabled then using Pause At Height with By Height can miss a trick as it will react to the first instance of the height specified for the pause even if it is only a Z-Hop and not the working height.  Adaptive layers can also be a problem for Pause at Height.  All that being said, I use Pause at Height a lot and it works fine for me but there have been issues.

[gr5 2,099]

The UM2+C has I believe two computers in it - an arduino based computer that controlls the steppers and accepts gcodes from... the second, more powerful computer (think cell phone).  The gcodes are all interpreted by the more powerful linux computer which then sends some of them as is over to the arduino based computer.

 

The display is controlled by the linux computer and the M0 requires more complication because the display and touch screen need to pop up a message and when you tap the screen the printer needs to continue.  Also it's nice to have the ability to control temp, maybe even change the filament, all while it's "paused".

 

So really the linux computer has to convert that M0 into an upward movement (so the hot end doesn't melt the part) and it needs to display a message and when you continue it needs to move back down and continue the gcodes.

 

My point is the M0 never gets to the arduino-like computer because if it did it would be bad (there wouldn't be any way to continue).

 

I think no one at Ultimaker has written all this code yet.  It's written for S3 and S5 I think but not UM2+C.  I hope they do it soon but I wouldn't hold my breath.  Ultimaker seems to be convinced that most of their clients (think for example factories making parts for the factory itself) don't need to pause a print and say insert a nut or magnet.  Many employees realize that "pause" is very very useful to many many clients but I don't think the entire management team is on board with this idea.  I'm not sure but that's my feeling.

 

Often writing the code and getting it working is the easy part - then you have to test the hell out of it (does it break if the heated bed is off?  should you cool the nozzle a little bit?  And heat it up again?  Do you want to implement a fancy filament change feature?  Or just make them slide the filament out and in?  Do you want to implement the MOVE feature to purge the filament?  Do you do a retract at pause and unretract at continue?  If they purge do you do a retract after purge?  And so on).

 

[LordTakeshiXVII 1]

I got a response from Ultimaker. 

 

Pause at height is currently not supported by the firmware of Ultimaker 2+ Connect. 

Maybe it will be implemented into one of the future firmware releases. 

 

I'll do my best to time pauses manually until this hopefully get's implemented. 

 

Thank you for your comments and discussions so far. 🙂