I have created this abacus for my daughter to keep track of her swimming laps.
Since the abacus stays on one side of the swimming pool, a black beat of the top row is worth 2 laps. A golden beat from the bottom row is worth 10 laps. In total 60 laps can be counted.

Print the beats first.
Print the frame standing on its side so the bars are pointing up. Insert a pause before it starts printing the upper leg so you can slide the beats onto the bars. After that let the print finish.
No supports needed when printed in this orientation.