Extruder Merger by mokash770

Last crawled date: 3 years ago

New version at https://www.thingiverse.com/thing:2808135
This part enables you to use 2 extruders with one hot end.
(1.75mm)
Iv'e tested it with a light6 and so far the concept works well, I just need to tweak the g_code a bit to deal with the excess material that hangs around after the purge of switching extruders.
You will need three 1/8 push fittings to connect this, the brass ones thread better for some reason but will need to be drilled to allow the bowden tube to pass through.
Search ebay for this part "PC4-01" to get the predrilled kind, although they may require some heat to thread properly.
As for firmware, if you want to use a ramps board in the configuration EFB (Extruder,Fan,Bed) you will need to make some adjustments to the pins.h file, you need to enable the second extruder under the EFB area by replacing -1 with something else, also you will need to change the thermistor pin for the second extruder to match the one of the first.
I have uploaded my configuration for a ramps 1.4, but use it with caution, everyone's printer is different, so endstops, bed leveling etc.... must be adjusted to your setup.
For the g_code, you will need to retract about 200mm before extruder change, and extrude at least that amount after.
this is what I have in cura so far.
;Switch between the current extruder and the next extruder, when printing with multiple extruders.
;This code is added before the T(n)
G91 ;relative positioning
G1 E-1 F6000 ;retract the filament a bit before lifting the nozzle, to release some of the pressure
G28 X0 Y0 ;move X/Y to min endstops, so the head is out of the way
G90 ;absolute positioning
G92 E0
G1 F10000 E-165
G92 E0
G1 Z+7.00 F{travel_speed} ;alow room for exes filament to pass
And after
;Switch between the current extruder and the next extruder, when printing with multiple extruders.
;This code is added after the T(n)
M104 T0 S215
M104 T1 S215
G92 E0
G1 F10000 E195
G92 E0
G1 Z-7.00 F{travel_speed} ;return to original layer hight
The speed of the retraction is important, to slow will stretch the filament in the path without clearing it.