Cupcake + Discov3ry Integration Wiki & Discussion Thread


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[Img] Where to access the electronics board containing the extruder motor driver(s).
Connector, cable, or wiring steps necessary for integration to electronics board.
Wiring schematic. What are the matching colour wiring pairs for the Discov3ry stepper motor compared to your printer? (Black, Green, Blue, Red pair with what?
[Img] The exact location of the connection for the extruder motor driver.
Please note all extra steps for wiring here if the integration for your 3D printer is more involved.

Describe any firmware changes necessary for the integration process. This could include settings like disabling the cold extrusion code, adjusting the EEPROM settings for the Discov3ry (typically ~10-100x default settings), hard coding XYZ offsets for a new nozzle, etc.

[Img] The mounting system you have utilized (link to .stl file if applicable)
Other hardware needed in the mounting process (Links to McMasterCarr are golden)
[Img] How to install the mount on the 3D printer (Include Tools required)
[Img] How to attach Discov3ry tip to the mount. (Is it adjustable? Any other special features that should be known?)

What are the ideal slicer parameters that you have found for a specific material? Layer height, speed, infill, etc. Please share a configuration file that you have successfully utilized, preferably using the slicer that is applicable to your 3D printer.

[Img Gallery] Successful prints – test prints or otherwise.
[Img] Printer and Discov3ry integrated together




Just received my paste extruder a few weeks ago. I’m having trouble installing it on an old makerbot cupcake running merlin firmware, we stripped out the extruder and just made a custom Mount to hold the nozzle; however I keep getting a MINTEMP error, even when putting M302 (enable cold extrusion) in the start gcode in cura. Is there something else I need to do, or some other setting I’m missing? I contemplated putting the extrusion thermocouple back in and just setting extrusion to 25 or something, is that all there is to it or am i missing something else? Thanks in advance…


Have you tried inputting M302 via direct g-code command to the printer? Have you confirmed via M503 that the M302 command took effect?

Some of the failsafe code for temperature is part of the firmware, so simply inserting M302 in the g-code file alone might not be enough.



Thanks Charles, actually my first guess was indeed the correct one - m302 was working fine, but the MINTEMP error relates to a interrupt that’s triggered if our marlin firmware doesn’t see a thermocouple at all in the extruder. I simply re-inserted the removed thermocouple and it successfully executed print commands. I still need to play with the extrusion feed rates, but for now I was able to demo an initial “test print” of a blob of acrylic caulk, see flickr album here:

or our public wiki project page at:

Two related / follow up questions: 1) I ended up shoving a block of wood in between the syringe and extrusion base as I couldn’t find a quick (non-software) way of raising / lowering the threaded bar - is there a way to change that height easily? I didn’t like to drive the extruder stepper too fast, as 2) the stepper motor driver we were using was hitting 60C+ when driving, potentially indicating it was straining to push the extruder motor. Is there a list of recommended / suggested stepper motor drivers? (This happened even if extruder was under no load, could also have been exacerbated because the acrylic caulk was quite viscous / difficult to push through the syringe, even manually).


That’s great to see you’ve got it working on the Cupcake! :smiley:

To answer your questions, 1) easiest way to raise/lower the threaded rod is to remove the allen key from the syringe gripper and turn the rod manually. Then when you have the desired height, simply re-align the syringe gripper and insert the allen key again. 2) We’ve operated the Discov3ry stepper motor for lengthy use printing numerous viscous materials and have not had an issue. I’d recommend checking the acrylic caulk as to its work time before setting. If the initial setting time (time to skin over) is short, like 15 minutes, that could be the problem – it means the material is becoming more viscous while you are still trying to print. An idea work time is about 45 minutes (30 minutes minimum).