The Mantis 9.1 design is a radical departure from version 8 and earlier. Most notably, the part count has been almost halved! The current design has 13 parts, all of which can be made with a handsaw and a drill press. Also, I’ve traded away my alignment free exactly-constrained design for extra stiffness. Several unsuccessful attempts to eradicate the last of the slop in the Z axis on version 8 lead me back to the world of over-constrained parallel rods. My previous attempts at an over-constrained design (versions 1-5) all failed because I was unable to make the rods sufficiently parallel to avoid jamming. What to do?
Mantis 9.1 CNC Mill - [Link]