Quarter Dispenser

Hi! I am Russell, currently in 9th grade. I have never like having to carry cash around and coins just make the problem so much worse. However as many things such as busses and vending machines around my area don't accept credit cards, I have found carrying quarters to be very useful. As a result I have come up with the idea to make a spring loaded holder inspired by Pez dispensers that can carry a stack quarters.

• 3D printer
• PLA filament for the printer
• 2x M3 nuts
• 2x M3 x 4mm screws

First I started with measuring the size of a quarter and creating a basic holder for them in Fusion 360. I then cut the model to make a removable cap so it could be loaded.

Going off this design I printed the body of the quarter holder. I printed these parts with a 0.12mm layer height and 15% infill. I then made sure a quarter fits nicely through the gap and the tube holds a good amount of quarters.

I created a few variations of springs with the coil feature in fusion 360. Above are 2 of the options I tested. The amount of revolutions and thickness of the coil affected how much the spring compressed and the strength. The final spring had a 3mm square cross section at 24mm in diamiter with 3 revolutions. It was printed at a layer height of 0.2mm and infill of 25%.

Finally, the spring is inserted into the bottom section, the nuts are inserted, and the quarters are stacked. The top then slips on and is bolted onto the top with the M3 screws.