For the Mountain Lakes Public Library Math Day I designed this mini abacus (65 mm x 65 mm) with five holes and enough room for 7 beads per rod. This is a great make and take project. The mini abacus 3d print takes anywhere between 25 and 40 minutes depending upon the number of walls you print with and infill%.

I prefer 3 walls and 35% infill, which at 75 mm/sec speed and .24 resolution, prints in 37 minutes.

To complete the abacus, use pipe cleaners as the rods and perler beads as the counters. The end of pipe cleaners can be sharp, so you can cut the ends and twist to reduce pointy edges.

If you would like to remix and make a larger version, make sure to keep the holes for pipe cleaners at 2 mm diameter.

Quick 3d Design Tip: I used Tinkercad to design. In order to have smooth, rounded edges, I use the BOX and adjust radius to .80 and # of steps = 12. If your print has issues with these design measurements, you can try a smaller radius, .50 mm.

Feel free to add a logo or saying. I easily fit "ML Makerspace" across the edge.