When it is running, this setup swaps tools on a CoreXY printer that already exists, enabling multi-material printing with quick switching, low cost, low effort and little wasted filament. For anyone who owns a machine and does not want a dedicated multi-tool purchase, that is a very appealing pitch.
The hardware is pleasingly simple. A machined metal carriage body sits at the core, located by a Maxwell kinematic coupling with magnets. The dock is a two-piece block with counterbored screw holes, vertical keyhole slots and round pockets for cylindrical neodymium magnets, and it secures the toolhead using M3 cap head screws along with those magnets. Spring-loaded pogo pins carry the electrics, and SpeedClips keep the multi-pin wiring tidy and serviceable.
Other choices stand out to me. Alignment runs through Nudge, an omnidirectional contact switch that senses physical nozzle touch in X, Y and Z, all driven by Klipper macros, with OpenFFBoard and TMC4671 chips in the mix. Reaching this state took patience: eighteen months of testing went into solving heat creep, where warmth from the bed, hotend and extruder motor lets plastic deform under screw pressure.
Two open points are worth flagging. Travel shrinks by 3mm per side, but only in the front corners, and that loss drops to nearly nothing when just one head is mounted. On top of that, the compatibility chart is not complete and still needs additions, and the maker is still working on linking or adding files to the main repository.
Project by Zruncho 3D. Watch it on their YouTube channel: