Coin Sorter for Optimized Speed

Sorting loose change is slow, boring, and easy to put off — so I built a coin sorter designed to make the job fast, automatic, and satisfying. This project takes advantage of gravity, simple geometry, and a streamlined layout to separate coins instantly as they roll down the track. Instead of counting and organizing coins by hand, this device does the work in seconds.

What makes it perfect for the Let There Be Speed competition is how efficiently it turns a slow everyday task into a quick, almost effortless process. The design is lightweight, easy to build, and customizable for any currency. Whether you’re cleaning out a drawer or prepping coins for saving, this sorter speeds everything up while showing off clever engineering in a compact form.

access to a 3D printer and a spool of filament. Also, can be built with wood, foam, or cardboard.

Choose your materials

You can build this with:

1. Cardboard or foam board.
2. Wood.
3. OR a fully 3D‑printed design.

Pick whichever matches your tools and time.

Write down the diameter of each coin you want to sort. Example (US coins):

1. Dime – 17.9 mm
2. Penny – 19.05 mm
3. Nickel – 21.21 mm
4. Quarter – 24.26 mm

You’ll use these measurements to size the slots.

This is where the “speed” happens.

1. Make a long ramp that tilts downward.
2. Coins roll from top to bottom.
3. Along the ramp, cut slots that are just big enough for each coin to fall through.
4. Smallest coin slot goes first, largest last.

Tip: Leave about .5-1 mm of wiggle room so coins don’t jam.

Cut a sturdy base for the ramp.

Add side walls so coins don’t fall off.

Prop the top up so the ramp sits at a smooth angle (not too steep or coins will bounce).

Mark where each coin should drop.

Cut a slot slightly wider than the coin’s diameter.

Test each slot with real coins as you go.

Place a cup/bin under each slot to catch the coins.

1. Glue the ramp to the frame.
2. Reinforce weak spots with extra cardboard or supports.
3. Make sure the ramp is smooth so coins roll quickly.

Drop a handful of mixed coins at the top:

1. They should roll smoothly.
2. Each coin should fall into the correct slot.
3. No bouncing, jamming, or mis‑sorting.

Adjust slot width or ramp angle if needed.

Label each bin.

Add color or decoration.