Z-axis belt tensioner with larger anti-squeaking pulley seat.

thingiverse

I'm aware that there are existing solutions, but this design boasts a wider pulley seat ensuring that no frayed edges on the walls produce squeaking sounds. To eliminate this issue, you'll need to insert two 3 mm washers between the walls and the pulley, one on each side. For assembly, you will require four M3 nuts and two 30 mm long M3 screws.