All MakerGear printers use Cast Tool and Jig Plate, aka cast aluminum tooling plate for the precision critical structural components (for those with knowledge of GD&T, each Datum is defined with respect to these components).  The tooling plate is machined with flat surfaces for mounting linear rails and tight tolerance holes for holding linear rods and ensuring orthogonality,   By installing these to our welded steel frames (M series printers) or riveted aluminum frames (Ultra One), we build the most robust, precise, repeatable, and user maintainable machines on the market.