Here's a concept of a coreXY 3D printer based on Prusa i3 MK3(S). It's not an official printer so don't expect any support from Prusa. Marlin 1 supports coreXY but some features could be malfunctioning.

Requirements

• Prusa i3 MK3(S)
• one extra ALU plate
• 6x extra 20T idlers (pulleys) (2 pieces are in the original printer)
• bolts & nuts for pulleys
• optional: extra bearing for steel rod (to have 2 on both sides)

Printing

Most pieces are printable without support. XY pulleys' home (attached to the frame) need some supports.

Building

You don't need new ALU extrusions. You can print connections and secure them by the original front and rear plates (you need extra M3 ALU profile nuts). Don't place the connection both on the same side but diagonally. This will make the frame more rigid.

TODO

• Z axis
• head to belt fixture + tensioning
• bed fixture
• electronics fixture (should be higher to handle shorter cables)
• FW config + fixing
• make idlers' home supportless