Printrbelt automatic printing with Polarcloud plugin

TLDR; A feature was shown with Polarcloud that autostarted the next print in a queue without user intervention. The code for this change was not made available but the developer has let me know what needs to be changed im just not particularly skilled with plugin editing and looking for the Octoprint Jedi to help a struggling Ewok out.

Hey all,

I have a Printrbelt (angled belt printer that can remove prints as they finish) that I am looking to get up and running and while investigating the software end I've found that there is a piece of the puzzle missing. Currently using something like Octoprint Print queue means you cannot add to the queue once you have started it essentially making it less of a dynamic system. A different option is Polarcloud which has an Octoprint plugin available and was the original recommended software by Printrbot and William Steele. William Steele showcased that the queue could be added to and reorganized at any time prior to the print starting and that it would automatically start the next print without user intervention. []. This is what im looking to re-enable.

Unfortunately with the closure of Printrbot, William did not finish publishing the changes to allow for autostarting. He did, however, give me information for what would need to change in the plugin code as everything is already setup on the Polarcloud side.

Would anyone be up for helping me make the edits?

Here is what I know needs to get changed, I have confirmed with the Polar cloud team that everything is setup on their end.

"There is a setting in the capabilities configuration that tells the cloud that the printer is capable of automatic printing. The string is "sendNextPrint".

Here is our protocol... look at 2.2.

Once you implement that, you can call the sendNextPrint command and it will automatically start the next job in the queue. (See 2.15 for details.)

{And 3.10}"


I'm not going to write plugins for Polarcloud, but you might be interested in the print queue I wrote for BlackBelt:

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Yes! I very much like this plugin however would there be anyway to make it so you could add to the queue while its actually printing? From what I saw once you commence the queue its locked in.

Not in the version I linked to above.

If I had installed Print queue through Octoprint plugin manager would I have gotten the version above? Or should I just uninstall my existing one and install via URL:

Do the latter. If you use the one via the OctoPrint plugin manager, you'll get the one I started with. Barely a line of code is the same in my version.

Awesome, any other features in your version? Is there a change log or anything like that? Thanks for pointing me in that direction, will give it a try tonight.

It is basically an entirely new plugin (and I should probably rename it).

  • Queue persists between browsers and is not cleared when reloading the page
  • Queue can be reordered by drag and drop
  • Gcode files can be dragged into the queue from the gcode list
  • Gcode files can be added to the queue as they are uploaded
  • It is possible to strip parts of the end- and start-gcode snippets between gcode files so the printer does not (start to) cool down between prints
  • Settings are moved to the OctoPrint settings dialog

My OctoPrint-Playlist plugin is similar, and was initially a fork of the PrintQueue plugin. If I remember correctly, you can dynamically add files/re-order files in the queue, etc. It was originally designed for a sandbox printer, hence the scheduling options.

Cool will take a look at that as well, safe to assume it automatically moves to the next queued gcode without user intervention? Neat that this was used for a sandbox plotter always wanted to get one built.