GT2 Belt Pulley Idler Mounts

SolidCore Kinematic Bed Setup

SolidCore Kinematic Bed Design

We recently started working on the SolidCore printer‘s bed leveling and mounting system. The z-axis uses a 3-point kinematic bed mounting with magnetic pivot spheres on each mount This properly constrains the bed at 3 points of contact. The pivot balls attach to the bed mounts and keep position by the weight of the bed. The steel pivot balls will slide along the dowel pins as the bed expands from heating up. 

3-Point Bed Leveling

Three point bed leveling uses three independently driven lead screws to level the bed and compensate for an uneven build plate. The Z-axis lead screws are used as the 3 points that make up a triangle, defining one plane. 

Three Points Make A Plane

The advantage of a kinematic bed mount is that the defined plane of the bed, a kinematic mount, is that the aluminum plate can properly expand without bending the plate.

Z-Brackets

Carriage Design

I've been working out the geometry for a modular y-carriage design for the SolidCore printer. I prefer to have the hotend and sensor interchangeable. Here's some different models I'm working on.

• Independent hotend/probe mount.
• Combined hotend/probe mount.

The carriage and gantry are designed to be light weight and strong. We currently use c-shaped aluminum stock because it reduces machining time. The reduced machining time and minimized waste helps but it’s a compromise. Thats going to change soon. We’ll probably make some changes such as reorienting the the y-axis linear rail into a vertical position similar to the RailCore but the current horizontal version will be easier to adapt an E3D Toolchanger. 

Carriage Assembly Mounted to MGN12 Linear Rail

Balancing the pull to the center of carriage instead above it or below seems to be more rigid and minimize deflection. The belts are somewhat within the same plane of the three linear rails to avoid rocking cantilever loads that other designs may have with the belts up high or down low.

Belt Anchor And Tensioner

The new carriage design has M2 tapped holes to mount the y-axis endstop switch and act as a self locking post. For now the motor mount plate has slots to tension the belts.