What MOD rack size to use?

[Norgmonster]

Sorry to chime in but i was wondering if the type of MOD (1 or 1.5) you use is decided by how heavy the gantry ends up being? If so then what is the limit?

[m_c]

Sorry to chime in but i was wondering if the type of MOD (1 or 1.5) you use is decided by how heavy the gantry ends up being? If so then what is the limit?

The deciding factor is cutting and acceleration forces, and if the chosen MOD size can handle the required torque/forces.
As part of that you also have to consider tooth engagement, as a larger pinion will have more teeth engaged at any given time so can handle more torque than a smaller pinion.

[Norgmonster]

Thanks for this info. I'm still working on the designs for my CNC Router so when i'm ready can i ask again?

:-)