@jay_s_uk They are used to handle an additional filament during the print. That filament is not printed but layed into the printed part during printing. The V Axis rotates the FFF-Nozzle around the center of the print-head where the nozzle for the additional filament is. The W-Axis controls a storage system for the additional filament. It is a big wheel that can increase and decrease its diameter, so the additional filament can be extruded and pulled back. That system is completely custom and wasn't developed by me alone.
