easy hand crank for Pastamatic

hand crank for pastamatic

a spool of bambu filament got away from my sister, and now needs to be respooled.  she wanted a hand crank, so I designed this one.

in particular, I wanted it to be easy to print and not require any extra hardware or supports.  I wanted it to be durable, easy to use, and easy to assemble—since I had to explain it over the phone.

I looked at other hand crank options, and none of them fit these requirements.  this design is significantly different from the ones I found.  in particular, I opted for a knob rather than a long handle, because I operate my pastamatic from the side, or close to the source side, and a long handle would be uncomfortable to use if I'm sitting in front of the side of the machine.  a long handle would make it easier to crank harder, but power is not helpful for this—speed and a comfortable turning motion are.

printing

• walls printing order: Inner/Outer/Inner (the tolerances are pretty tight)
• 5% infill was fine
• 3 walls should be okay for all parts, but if you're feeling nervous 5 walls for the “spindle male crank” will be really strong
• the crank action absolutely requires a regular “spindle clip” and a “drive spindle clip” on the driven spindle, on the target side.  if you don't have spindle clips on the source side and the lead screw, I recommend printing 4 spindle clips.

the original pastamatic calls for 100% concentric infill for “spindle male driven” (the equivalent to “spindle male crank”, here).  this is because the infill reduces the amount of material connecting the hex socket with the crank.  in the case of the “spindle male crank”, the connection to the spindle is much stronger, so 5% infill and 3–5 walls should be sufficient.

assembly

• slip the “crank shaft” through the “knob”, with the flat side of the knob up
• insert the end of the crank shaft into the hex hole on the “spindle male crank” arm
• put the “c-clip” down on the crank arm, with the flat side down, and press it onto the end of the crank shaft (as shown in the picture).
• the spindle clips work best when the pastamatic pins are inserted as shown in the picture