CAD Design In Fusion 360
All Metal Parts
Our long term goal is to is to build a modular platform, not just a printer. Think of it as an ecosystem of parts that can be arranged in different configurations and adapted for unique applications.
Triple Z-Axis / Belted Z
We’re planning to use a 3 independent z-axis setup on the SolidCore 3D Printer. I’m not an engineer but I think that the belt and pulley ratio gives the steppers more torque and increases resolution. The belt to lead screw arrangement also minimizes and vibrations that might be transferred from the motors to the z-axis. Each lead screw will be constrained by an MGN12 linear rail. With the Duet Wifi we can drive 3 steppers and run an auto bed leveling routine using a proximity sensor or probe.
Single Z-Motor vs Triple Z-Motor
The typical core-xy 3d printer parts arrangement has a single NEMA 17 stepper motor with the belt routing to all two or three lead screws which move together in sync. Originally we were working on a design that used this single z-axis motor configuration. But after having trouble sourcing the belt that was the perfect length I decided to just go with three stepper motors similar to the HeVort printer or Jubilee tool changing core xy platform.
Duet 3 Mainboard H6C - RepRap Firmware
RepRap Firmware: Independent Z Motors
Many 3d printer users frown upon the idea of multiple steppers for independent z motors due to syncing issues. But with a good electronics setup like the 32 bit Duet board and the RepRap Firmware keeping the three lead screws in sync should be fie. When powered up stepper motors tend to jump to the four steps that match the phase current. Some will jump forwards or backward after a number of power cycles.