Bulldog XL Mount for UM2 Ultimaker 2

Mounts Bulldog XL Extruder to Ultimaker 2 using original extruder screw holes. No drilling required!

3D printer parts and enhancements

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    Print the mount in whatever material and color you want. I used Hatchbox Black PLA @ 50% infill and 3 perimeters/shells and 3 top/bottom layers. I used Simplify3D to do the slicing @ .15mm layer thickness and printed with support. The best results will come with the motor face part down against the bed. It took about 2 hours to print on a Prusa i3 @ 40mm/sec.

    To wire up the motor to the original UM2 board I cut off the original extruder motor wires about 75mm from the board connector. I added my own connector in case I wanted to put the original back on again. 
    Wire it up like this: 
    UM2 --------------------------- Bulldog XL 
    Black -------------------------- Brown 
    Green ------------------------- Red 
    Red ---------------------------- Yellow 
    Blue --------------------------- Blue 

     You will need to change the steps/mm for the extruder to 495. You can do this by downloading the latest version of Tinkergnome firmware here: https://github.com/TinkerGnome/Ultimaker2Marlin/releases

    Open up Cura and goto Machine->Install Custom Firmware and select the TinkerGnome firmware .HEX you downloaded.

    Then on the UM2, Advanced->Preferences->Motion Settings->Axis Steps/mm and change the value for E to 495.
    -EDIT: Forgot to add the support bracket for the planetary. 
    -Take the extruder apart, remove the black spacer and replace with this one. 
    -Now it will have the proper support on the back end of the motor assembly.

    Materials and methods

    One (1) Bulldog XL Extruder (obviously)

    Eight (8) M3 screws 20mm long

    Eight (8) Nuts & Washers (for mounting motor and to UM2)

    One (1) M5 x 12mm for top part of mount

    One (1) M3 x 12mm for top part of mount

    About 75-100mm of heat shrink to tidy up stepper wiring



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    869895cdecbaeba230a187715a18d53b?default=blank&size=40taylan added this to the aaa collection ago
    D6c932f8be282dc4621b9b02da4d44eb?default=blank&size=40WiseOldOwl commented ago

    I upgraded to the UM2+ - so not using the Bulldog right now. HOWEVER...I am looking to do a Mark2 conversion for dual extrusion & the Bulldog would be ideal for that.

    E7dff2cef6859d38b8af5761be494e70?default=blank&size=40karladam1234 commented ago

    How are getting on with the Bulldog XL conversion?

    Any good?

    5953aefc465f884ff7f9ad451e25434f?default=blank&size=40ollifant added this to the printer collection ago
    Cb013efa08026866713ee8ea4f98a733?default=blank&size=40Sergey Fedorov added this to the Ultimaker 2 Upgrade collection ago
    D6c932f8be282dc4621b9b02da4d44eb?default=blank&size=40WiseOldOwl published this design ago