Documentation: Useless Box Kit

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      1. Choose a model to use with your kit:
        • Browse the 3D models above
        • Use associated link to download the ZIP file
        • ZIP files contain STL ready to print and STP files for easy customization
        • Print your chosen model:Print the STL models or customize the included STP files (recommend Fusion 360)
      2. Prepare your Useless Box Kit:
        • Install M3 brass inserts into the 4 holes in the box frame. 2 for hinge, one on bottom for limit switch, one for motor brace, one in motor arm
          • Carefully use a soldering iron to guide the brass insert into position and gently press it into the recess
          • Note: Make sure the insert is level with the surface and do NOT over-tighten bolts
      3. Prepare battery, motor and limit switch wiring:
        • Cut only one positive and one negative wire from the opposite battery holders, leaving about 40mm and solder them together in series
        • Solder the 2 cut battery wires to the motor tabs
        • Cut 3 pieces of scrap wire to 80mm and solder two of them to the outside leads of the limit switch
      4. Secure printed arm to motor shaft with m3x8 bolt
      5. Slide motor and limit switch into their locations then secure limit switch with printed holder and m3x8 bolt
        • Note: bending wires at 90 degrees to limit switch leads, then carefully positioning switch makes installation easier.
        • Note: limit switch lever faces away from motor.
      6. Slide one battery holder into case, adjust wires to come out the between battery holders, then slide second battery holder into case
      7. Secure motor with printed motor brace and m3x8 bolt, feeding motor wires behind brace
      8. Install toggle switch into printed switch lid and tin the leads with solder
        • You can do the entire solder job by securing the toggle switch in helping hands before installing in printed switch lid
      9. Solder wiring to toggle switch:
        • NOTE: Do NOT overheat the toggle switch leads with soldering iron. If adjusting a bad solder joint, allow lead to cool first before reheating lead up as too much heat can damage the toggle switch
        • Start by using the 3rd 80mm scrap wire cut earlier and soldering it to top left and bottom right leads
        • Now solder limit switch to bottom left and top right leads allowing the lid to hang behind the box, polarity doesn’t matter
        • Solder the negative battery lead to the middle left and the positive to the middle right leads, polarity DOES matter
        • Finally, solder the negative motor wire to the bottom left and the positive lead to the bottom right
      10. TEST the operation:
        • Adjust the motor wires so they route behind the toggle switch and stay clear of the printed motor arm
        • Flip toggle switch away from viewer as seen in assembly photos
        • Temporarily place switch lid on case to check motor arm clearance to ensure arm doesn’t touch the switch leads or wires
        • Install bottom battery by manually raising motor arm inserting positive end first then compress negative spring with small screwdriver
        • Install top battery and be prepared for the arm to swing downward into limit switch!
        • Test switch to ensure it is operating as expected
        • Troubleshoot if necessary:
          • Carefully inspect all connections to ensure soldering is clean and not bridging switch leads
          • Motor turning in wrong direction, de-solder the wires from the motor and switch or double check wiring
      11. Secure printed flip lid and switch lid to case using m3x8 bolts
      12. Try different prints or design your own!
        • Note:  Not all 3D model designs use all parts. 
        • If you design your own, be sure to share it with the community in our Thingiverse group!

      Upcoming designs may include: Symbols, Logos, Treasure chest… What sounds cool to you?

      Parts List:





      M3 x 8mm Bolt


      M3 x 4mm Insert


      AA Battery Holder


      DC Geared Motor


      Toggle switch mini DPDT 3A


      Limit switch 1A 125v norm open


      26 awg wire 400mm, random color


      Hex Key (2.5 mm)