Educational Balance Scale - learn numbers

The Educational Balance Scale is an educational toy for kids to help them understand numbers and their significance. The number blocks and stars are proportionally weighted: Block 5 equals Block 2 + Block 3, or 5 stars. In addition, the number blocks are proportional in height to each other: If you put Block 1 on top of Block 3, it will be as tall as Block 4.

The model is a fairly simple print, but it can be tricky to make the pieces weight the right amount. 

Printing:

I printed everything with PLA. It's a fairly simple print, and everything can be printed without supports. No AMS or MMU required. 

The tricky part is probably making the different parts weigh the right amount. To do so, I first printed a star and weighed it. Then, I used the built-in slicer function that lets you see the estimated weight of your print (used filament in grams). Be careful to set the correct density for your material in the filament presets. It can usually be found in the technical specifications of your filament.

The stars are printed with eSun PLA Magic, which is a dual-color filament. To get the cool three-dimensional effect, I set the top and bottom infill pattern to concentric in PrusaSlicer.

To make the numbers white on the number blocks, I added a filament change before the last layers.

The other parts are quite straightforward.

Assembling:

Just insert the 3D-printed bolts into the holes of the parts and screw on the 3D-printed nuts by hand.