Here is a preview of all the parts you will need to complete this project.
Step 1: Print the Parts
Attached are the .stl files. Print all of these files in order to assemble the gumball machine. If you are limited on resources (plastic, time, etc), then you can scale all the pieces by 0.5. Also, scale the drum a little bit smaller than the body to ensure that it fits. All of the following pieces can be printed without supports except for the fitting tube.
The gum ball machine body was printed in red PLA plastic material and was scaled down by 0.5 in all planes (x,y,z). We suggest printing this in ABS for smoother texture.
The drum was printed in green ABS material and was scaled down by 0.45 in all planes (x,y,z) to ensure that it fits in the body.
The coin face was printed in light pink ABS material and was scaled down by 0.5 in all planes (x,y,z).
The knob was printed in white ABS material and was scaled down by 0.5 in all planes (x,y,z).
The fitting tube was printed in gray ABS material, with supports.
The plastic shot glass (2.3 fl oz (68ml)) was bought from Walmart.
These pieces were printed on the LulzBot Mini and other 3D Printers.
Step 2: Assembly
First, trim off the legs of the coin face; this can be done using regular scissors. This is necessary because the legs may not fit into the body. Then, push the knob of the drum through the hole in the center of the coin face. Make sure to push it all the way through. Now that the coin face and drum are attached, glue the knob to the drum. The knob should fit, but will require a tiny amount of gorilla glue in order to stick to the drum. Make sure that the glue does not reach the coin face as this will keep the drum from rotating. Set this aside to dry for approximately two hours.
In the meantime, the two latches at the top of the red body need to be cut off. This can be done using a band saw. This step is necessary for the fitting tube to fit on top of the machine body. After printing the fitting tube and removing supports, the piece should easily fit into the machine body. It should be snug, not loose, but easy to remove.
Now the drum, knob, and coin face should be dry. The coin face can be glued to the machine body. This was done with proxy, to minimize waiting time but it can also be done with gorilla glue (which needs two hours to set).
The last step is to place the shot glass, upside down on top of the fitting tube. It should be a perfect fit and can be easily removed for loading the candy machine.
Step 3: Candy
The last and most important step is to load the candy machine with your favorite candy! Fill the shot glass with the candy and turn the machine upside down to load it and keep from making a mess. The candy pictured is Mini M&Ms and these are perfect in size. Any other small candy could also be used. Turn the knob and the candy will fall out.