2" Axis

From the BOM, we have -

BOM

Axes - 32' total (8 rods of 3', 4 rods of 2' for z) - $640
Frame - ~~1/2"x6"x6" angle -$20/ft; 4x4x1/2 tube - $30/ft - 36 ' - $720 or $1080~~. Use flts to make 6-sided space frame per OSE industry standards
Oil-impregnated 2" bushing - 8000 lb+ lateral force capacity- $9.41 - [1]. $240. 24 needed, 18 minimum. 2" is huge and weighs about 1 lb each if naval bronze acc to Metal Weight Calculator.
Belts - see GT2_Belts#Belt_Drive_Cost - $12/foot x6 = under $100.
Motors - 6 Geared Down Stepper Motors at $30 each -