I'm new to everything CNC, but I'm interested. I've had my eye on the C-Beam kit available on the OpenBuilds parts store. The usable dimensions look good... except... there's only 1.2 inches available on the Z-axis... The machine is built from 3 linear actuators. Two 500mm linear actuators for the X/Y axes and one 250mm linear actuator for the Z axis. It looks like (though I'm not an engineer) the Z axis is limited because the actuator would get in the way of the router. My question is, if we had two linear actuators on the sides (like that of a 3d-printer) for the Z-axis and mounted the router to the cross beam actuator, would that result in a weaker system?... Do we not see CNC machines with the Z-axis actuators on the sides because something's lost? Or is it cost thing? thanks in advance
https://openbuilds.com/builds/c-beam-big-mouth.3625/ https://openbuilds.com/builds/dream-to-practical.3722/
The c - beam was designed for cutting aluminum plates and other 2.5D items. Therefore, you do not need or want a long z-axis because you would introduce more deflection in that axis. If more depth is desired, you could lengthen the sides. My fear of having two linear actuators is that getting them perfectly level all the time would be a pain. That is the part that causes me the most grief with my 3d printer. If the two were slightly off, all your parts would be parallelograms when looked at from the sides rather than having 90 degree sides.