Connecting to Ocroprint:
If you’re inside of denhac connected to the Wi-Fi, you can access the instances using this URLs:
- Lulzbot Mini: http://mini.inside.denhac.org/
For the Lulzbot Mini, OctoPrint is running off of a Raspberry Pi (https://www.raspberrypi.org/) connected to the printer via USB.
Uploading a model:
OctoPrint previously had a built-in slicer, but that was difficult to maintain for both us and the developer of OctoPrint, so the built-in slicer has been removed. Instead, you’ll need to use Cura Lulzbot Edition for the Lulzbot Mini See the sections below for more information on that.
Currently, all users have access to any other user’s folder. Hopefully, a future change will help with that, but for now… no peeking. The “Files” menu (see the image to the right) normally holds everyone’s folder, but I’ve already clicked in through my folder. If your folder doesn’t exist, click the create folder button, give it your username, and then click through.
Once you’ve got your sliced gcode file you are ready to import into Octoprint! We keep a bookmark within Chrome titled “Mini Inside” This will take you to the Octoprint app. If this is your first time logging in you’ll want to create a folder for yourself to store your print. Please be respectful of other people stuff and dont add or delete anything in someone elses folder. Now that you have your folder, Click the (upload?) button. Navigate to wherever you saved the object and (import?)
Loading and unloading the filament:
You will need to swap out the filament whenever you want to use a different color or material. On the “Control” tab you can use the x access (left and right) directional arrow controls to center the print head to give you more room to access the printhead and filament feed. If you need to adjust the height of the print head use the up and down z arrows. To move the print bed use the up and down y access buttons. The home button will return the print head to its “home” position.
First we need to unlatch the clamp that holds the filament in place. The latch is held in place from the pressure of the springs. Pull back and up on the latch against the springs until the latch clears the top corner of the gray clamp.
Now we must heat up the printhead to allow the removal of the hardened plastic. In the pictures I am using ABS which we can see on the spool label has a print temperature of between 220 and 260 degrees celscius.
To remove the filament you can either use the preset temperature under the dropdown of the target temperature panel on the temperature tab pictured here:
or you can set it manually to within the recommended print temperature of the material then click the checkmark button.
In the temperature tab you will see the target temperature as a faded line with the fully colored line representing the actual temperature. Once the actual temperature line has climbed to meet the target temperature line we can safely remove the filament. To do this gently pull the filament till it clears the housing.
Once you have removed the filament be a good citizen and thread it through the hole in the spool for the next user.
Often the filament will not remove cleanly from the printer. If the filament you are loading does not have a clean angled tip, use a pair of clippers to cut the end off.
Now that the filament has been loaded we need to purge any remaining filament of the previous spool. To do that first make sure that the print bed is centered under the printhead. This can be done by adjusting with the arrow buttons within the “Tool” panel of the “Control” tab.
Once it is centered we can begin purging the remaining filament. 25 mm is the recommended amount to extrude at a time while purging however it will often take several clicks to fully purge.
Once the filament no longer shows traces of the previous color you are set to start using the new filament.
If you are simply changing the filament please without actually printing, remember to now set the temperature to 0 on the temperature panel or select “Off” from the dropdown:
The Lulzbot mini has a 152 mm x 152 mm x 158 mm print area. The print bed is heated and uses a PEI sheet to help the plastic stick well to the bed. It uses 3 mm filament (2.85 mm is the same) and has a 0.35 mm nozzle.
Before printing the mini will execute the homing sequence. We advise monitoring this process as you will sometimes be able to catch a failed print early. During this process the printer touches the metal contacts at the four corners of the bed moving counterclockwise to orient itself in space. It will then wipe the nozzle on the cleaning strip located at the back edge of the bed. The print head then does a dog leg up and to the left which signifies the end of the homing sequence. If any of these steps do not occur then you may want to consider canceling the print and retrying. If the homing sequence is continuously failing and the print is subsequently failing please contact a printer manager to perform maintenance.
Once the homing sequence has completed successfully we recommend monitoring approximately the first three layers of the print to check for other unexpected behavior. The majority of failures will happen within the first three layers so monitoring these will prevent you from returning to a smoldering pile of plastic ooze.
Now your print should proceed successfully. If at any point you notice that the print has gone awry you should cancel the print, clean the print bed and start over. Unfortunately this does happen from time to time. If this begins to happen consistently please contact a printer manager who will fix whenever they are able.
When the print has finished please remember to log out of octoprint and shut down the printer using the red button on the front of the frame.