I've seen a few candy machines (mostly based on the same model), but most of them have a hard time actually working with candy. 

This new design is much better at getting candy to actually dispense by including a large feed agitator and increases the size of the catch tray to reduce the frequency of spilling. 

Depending on what candy you're dispensing, you may need a different chamber depth or agitator size. I recommend you use the largest agitator that's still smaller than the dimension of the specific candy being used. If your candy jams between the shaft and the body, use a slightly offset chamber size. 

The “Shell” piece is also separated from the main body to allow printing the shell in shiny silk PLA while printing the body in a more solid material like standard PLA. The knob also dovetails with the main shaft to allow for the same material selection. 

Printing tips:

• Print the knob and frontpiece on silk PLA with the front oriented tray-side up. Use a tree support on the tray for a smooth inner lip.
• Print the shell with silk PLA. Make sure your seam is on the back!
• Print the main body and shaft with cheap PLA or PLA+. (These are not visible except through the dispenser hole.)
• If your jar rim doesn't fit snugly, print the lid grip piece (see below.)

Assemble the body in order:

1. Start with the body
2. Pressure-fit the mason jar rim into the top. Make sure it fits tightly: use the provided optional lid grip (cut in half, if needed) to add additional pressure if needed. If this isn't tight enough, picking up the machine by the jar can spill your candy.
3. Slot the agitator crescent onto the main shaft
4. Insert the shaft and agitator into the body
5. Slide the shell over the body
6. Fit the frontpiece onto the front loosely, then slide the shaft out through all three holes and attach the dovetail knob.
7. Slide the completed knob/shaft/agitator mechanism back into place. Screw the M4x8mm screw into the back to keep the shaft from sliding while still allowing free rotation
8. Attach the frontpiece with the M2x4mm screws
9. Attach a filled mason jar

Requires:

• 3x M2x4mm screws
• 1x M4x8mm screw