Graphtec CB-09 Drag Knife Mount for Ender 3 HeroMe or similar

thingiverse

This is a drag knife mount to facilitate vinyl plotting on a Creality Ender 3 Printer. The drag knife is spring-loaded with a simple rubber band and a cap to keep the rubber band from interacting with the drag knife adjustment screw. The mount is designed to remain on the printer and not collide with the end stops. The mount is higher than the printer nozzle, so once you remove the drag knife the printer can print as usual. Changing modes can be done in a couple minutes by replacing the print bed with a sacrificial plate, dropping the knife into place and hooking the rubber band over it. This design is compatible to the accessory mount of the HeroMe Fan Shroud Gen4 found here: https://www.thingiverse.com/thing:3182917 The fan shroud I personally use is the Red Squirrel compact Fan shroud: https://www.thingiverse.com/thing:4170231 The idea of using a rubber band to spring load the mount comes from Andreas_Botti who has designed a mount that replaces the printer Hot End: https://www.thingiverse.com/thing:4441625 The drag knife has a bit of wiggle room in the mount which can be fixed by wrapping a bit of clear tape around the drag knife body. There will be a little bit of flex in the mount if used with a different fan shroud than the RS compact, I recommend designing your own glue-in spacer/stabiliser or just filling the space between the fan shroud and drag knife holder with hot glue. The file plotknifestabiliser(1).stl is a simple spacer that slides between the fan shroud and plot knife mount and is glued in place with some CA glue or similar. It helps a lot to provide more rigidity to the whole unit for finer plotting work. As for the process of getting the plotting commands to the Ender 3, user LouBlue provides a well written guide under their design for a solid CB09 mount for the stock ender 3 fan shroud: https://www.thingiverse.com/thing:3709721