Ratrig Toolhead V-core 3.1 Filament Cutter

Hardware Needed:

• #4 cutting blade

• 2 M3x16 hex screws

• ballpoint pen spring

To make this design work there are some software changes needing to be made. 

I increased the size of the bed to 410 in the X direction in the stepperX section of the printer.cfg file.

[stepper_x]
position_max: 410

I also changed where priming takes place to be to make sure the new X value would cause an accidental partial cut during priming.  I did this my changing the offset from 5 to 10 in the x direction in the [gcode_macro PROBE_FOR_PRIMING] and [gcode_macro PRIME_BLOB] macros. However I found a quicker way that does require modifying the macros themselves. In the printer.cfg file add the following under the RatOS macro section:

[gcode_macro RatOS]
variable_nozzle_priming: "primeblob"
variable_nozzle_prime_start_x: "min"

This will move the primeblob from the side with the filament cutter to the side with the endstop limit switch.

I changed how the spring is held from BojanL's system of being under the fan shroud, but still kept the swing arm style cutter with a number 4 blade. My spring is now mounted under neath the extruder. The swing arm is also heavily modified for a shorter actuation of the blade. It is also designed to work with the stopper from thenaimis's filament actuation block at the end of the axis. I did modify the dimensions of that stopper for this design. 

Both BojanL's and thenainis's designs sacrificed print area in the X direction which this design overcomes.