RatRig V-Core-4 - Replace front nozzle wiper with A1 mini silicone brush (+MACRO)

The stock VC4 (IDEX) design for front nozzle wipers are really bad.  This modification uses the very-well-designed silicone nozzles brushes used in the Bambu A1 mini printer, combined with a custom macro for heated nozzle cleaning.   

The macro will do the following (demonstrated in video below):

• Homes the machine if needed
• Activates IDEX_MIRROR (if you used MIRROR=1)
• Heats nozzle(s) to MAX_TEMP  (default 245C)
• Retracts the filament 5mm
• Disables heaters, turns on fans (to cooldown faster)
• Does are 5-pass wipe sequence every 6 seconds until the nozzle(s) drops below MIN_TEMP (default 150C)
• Turns off fans, reactivates IDEX_SINGLE if necessary (should update to save and restore previous state)

INSTRUCTIONS to use this:

• Print the brush mounts in a temperature-tolerant filament (it'll be very close to the bed). 
• Get some A1-mini silicone brushes (must get A1-mini, not regular A1).  They are consumables, so get more than 2.  You can get them for about $1-2/pc on amazon:
  • I used these: https://www.amazon.com/dp/B0DNF8F2H8?th=1 
• Download nozzle_wipe.txt (it should be .cfg but printables won't accept .cfg files).  Rename to nozzle_wipe.cfg and upload it in mainsail next to your printer.cfg.
• Add the following to your printer.cfg

[include nozzle_wipe.cfg]

[gcode_macro NOZZLE_HEAT_WIPE_PARAMS]
# ADJUST/TEST THIS VALUE!  Z-height of nozzle wipe wrt to last bed probe.  
# The brush mount has clearance for small negative Z-values, and motion 
# shouldn't go over the bed, but still be careful and test
variable_brush_z_mid: 0.5 

# These other vars are the most likely to need changing/tuning, especially 
# for initial testing of the macro (raise z_mid, lower wipe speed)
variable_wipe_speed_mmps: 150
variable_cycle_time_sec: 6
variable_min_temp: 150
variable_max_temp: 245

# See nozzle_wipe.cfg for other variables you can adjust

• After restarting, the use the following calls (can create mainsail buttons for them):
• NOZZLE_HEAT_WIPE MIN_TEMP=150 MAX_TEMP=260 TOOLHEAD=0
• NOZZLE_HEAT_WIPE MIN_TEMP=150 MAX_TEMP=260 TOOLHEAD=1
• NOZZLE_HEAT_WIPE MIN_TEMP=150 MAX_TEMP=260 MIRROR=1

First time you run the macro, keep your finger on the e-stop/power.  I've used this macro a lot, but I might have made oversights for other printer builds.  Feedback welcome.

NOTES:

• USE AT YOUR OWN RISK!  The brush mounts are designed so that the highest point of the rigid mount should be level with the bed (top of the brush is above the bed), and they have small recesses along the wipe paths to provide extra clearance to avoid collisions.  But who knows.  Raise z_mid and lower speed the first couple times.
• This also allows using a slightly negative Z-values for your wipe level if you find it beneficial.  Again be careful.
• The macro uses a safe-z-height of 8mm, and should never enter the space over the build plate. 

See the following short video: