Z-axis pulley division:

• 200 step per revolution motor (1.8°)
• Stepper shaft has 16T pulley -> driving 80T pulley -> driving 20T pulley -> connected to belt
• Reduction = 5:1
• Final 20T pulley pitch diameter = 12.73mm (reference)
• 12.73mm * pi / 200 / 5 = 0.03999mm

Each full step should move z-axis 0.03999mm (a number that divides into 0.2mm would be better, but it should be close enough).

Can be divided down with microsteps 1/2, 1/4, 1/8, 1/16: 19.996, 9.998, 4.999, 2.4995um

6mm belt on first stage, then wider 10mm belt on second stage for higher load:

• 6mm = 2.8kg working, 56kg breaking strength
• 10mm = 4.4kg working, 88kg breaking strength

Hopefully bed weight will be <4.4kg.