Simple Balance

I wanted a balance to use in my maths tutoring. The equals sign (=) is in fact a mathematical balance point, having a physical representation of this abstract concept can help students make sense of algebra. 

After reviewing other balance/scale designs I realised I needed a design that could quickly dismantle and be robust enough to transport.  I had printed a fancier design previously from makerworld but it was far too fragile. I thought I could make my own version and pleased with my first design in FreeCAD, I thought it worth sharing.

Assembly is trivial as seen by the photos….but you will need a steady hand and a vibration free surface! The curved beam can be placed on the triangular base point.  It can be shifted left or right to “zero” the vertical needle in the groove.  Next you need two steady hands to lower the weight holders at each end of the curved beam simultaneously. It takes some skill to adjust the positions to get the vertical needle in the centre of the groove.  Younger children may need help, older ones will hopefully find this fun.

As there is very little friction in the 3 pivot points the balance is surprisingly sensitive.  If you swing one weight holder gently you can even get some symapthetic resonance in the second holder… an extra physics demonstration for free.

The model photographed was printed in Bambu Labs Matte PLA. The design is very simple and quite tolerant to a range of print settings.