When choosing what size to make your machine, start with the build area. This is the area your tool can reach. Smaller machines are more rigid. The more rigid a machine is, the easier and more forgiving it is to use. This gives you a larger acceptable feeds and speeds window. More rigid also means it will be faster and more accurate with the right settings. Every millimeter counts but the Z axis has the largest effect on rigidity. For a Primo MPCNC, 81mm is the shortest and I highly recommend that. More sizing details on this page.
Metric (mm)
Imperial (inch)
Primo
Burly
Full range of motion (pen, laser, drag knife, Makita RT70x, etc)
Dewalt DW660
52mm & 55mm Spindle
!!! note “* Tool Choice” Larger tools may collide with the side rails and restrict movement before the MPCNC reaches its full range of motion in X and Y. Select your intended tool to account for this difference in the following dimensions:
mm x
mm y
mm z
|Length (mm)| Qty | Name | |————————————–|—–|——| ||2|x rails, sides| ||1|x rail, gantry| ||2|y rails, sides| ||1|y rail, gantry| ||2|z rails| ||4|legs| ||total needed| total tube length assuming 3mm kerf|
|Length (mm)| Qty | Name | |————————————–|—–|——| ||1|leadscrew length| ||2|belt length along x| ||2|belt length along y| ||total length| belts (all 4)|
|Length (mm)| Name | |————————————–|——| ||x table size (outer edges of feet)| ||y table size (outer edges of feet)|
|Length (mm)| Name | |————————————–|——| ||x| ||y| ||z| ||clearance to remove z axis|