Sourcing
After my bad experience with the “Cyclops/Chimera” clone (2-in-1 with mixing capability), I purchased (June 2019) the improved “Cyclops” which resembles the “Cyclops NF 2-in-1” or “LERDGE 2-in-1 V2” , so I name this variant “Cyclops NF 2-in-1“:
which can be ordered at AliExpress (affiliate links):
- SANBrother Improved Cyclops (my source) or
- LERDGE 2-IN-1 V2 (slightly different screws holes to fasten heatbreak),
and uses E3D V6 nozzle (clone) and 30x10mm fan on top. The two mounting holes are 24mm apart and fit the Prusa i3 X-carriage.
Further, the two filaments cannot be mixed like the original Cyclops but either filament A or B can be fed into the nozzle, but not both at the same time. Also, one can print with one filament solely, a 2nd filament must not be present.
Pros:
- affordable
- simple setup
- single filament printing possible without 2nd filament being present
Cons:
- cannot mix colors
- long retraction required for tool change (>34mm)
- long transition purge (~55mm)
- custom PTFE or nylon piece in the heatbreak (not easy to source)
- uncoordinated retraction can cause one filament blocking another
Model & Part Cooler
I quickly modeled the heatsink in OpenSCAD:
so I was able to adapt my Parametric Part Cooler with following settings part_cooler(name="cyclops nf",m=30,wx=25,yoff=10)
:
and the printed assembly:
Download
https://www.thingiverse.com/thing:3680090
Full Assembly
I finally turned the heatblock around (from the default orientation), so I could see the nozzle better and the LED strip shining more direct on the nozzle and bed.
Operation
The long tool switching retraction of > 34mm imposes quite additional risk of jamming combined with temperature sensitivity: depending on the temperature the pulled back of end of filament changes shape, and may not able to re-enter at next tool switch – so I’m a bit skeptical on the reliability – time will tell.
As I use print3r
solely (without GUI), I set following in the printer profile:
# -- slicer=slic3r, slic3r-pe and prusa only: retract_length_toolchange = 36
and a small macro named e2-nf-t1.ini
for my Ashtar C #1 (380x400x380) Core XY style:
prepend_gcode="G91\nT0\nG1 E20 F100\nG1 E-36 F3000\nT1\nG1 E36 F3000\nG1 E60 F100\nG90\nG92 E0\n" end_gcode="G1 Y{$machine_depth-10} F6000\nG92 E0\nG91\nG1 E-2 F2000\nM104 S0\nG1 E-36 F3000\nT0\nG1 E36 F3000\nM84\nG90\n"
which I use as print3r @e2-nf-t1 ...
in case I like to print with 2nd filament only:
- start:
T0
: purge 20mmT0
: retract -36mmT1
: forward 36mmT1
: purge 60mm- reset E meter and go back to absolute positioning/extruding
- end:
- go back to Y380 (absolute)
T1
: retract extrusion -2mmT1
: retract -36mm quickT0
: forward 36mm quick- switch off heating and motors
This way I keep T0
as default, and on-demand switch to T1
only with @e2-nf-t1
macro in operations. One case is not covered: if I abort a print then T1
is still active in the printhead and manually needs to be retracted (future print3r
version will resolve this).
print3r --device=tcp:printhub:0 --printer=ashtar-c-1-e2 --random-placement --scad --slicer=cura print 'for(i=[0:2]) translate([50*i,0,0]) cylinder(d=5,h=40)'
Comparison Dual/Multi Color/Material Extrusions
blue = relevant positive
red = relevant negative
Independent Dual Extrusions (IDEX)
- complex setup
- moderate cost
- non-mixing
- dual nozzles
- dual heatblocks
- dual heatsinks
- normal retraction
- no purge block 1)
- no oozing over print
- no inactive nozzle traveling
- reliable 2)
★★★★★
Dual Hotends 2-in-2
- simple setup
- low cost
- non-mixing
- dual nozzles
- dual heatblocks
- dual heatsinks
- normal retraction
- no purge block
- inactive nozzle oozing over prints
- inactive nozzle travels over print
- moderate reliability
★★★★★
Chimera 2-in-2
- simple setup
- clone: low cost
- original: high cost
- non-mixing
- dual nozzles
- dual heatblocks
- single heatsink
- normal retraction
- no purge block
- oozing of inactive material
- inactive nozzle travels over print
- moderate reliability
★★★★★
Cyclops 2-in-1
- simple setup
- clone: low cost
- original: high cost
- mixing
- single nozzle
- single heatblock
- single heatsink
- normal retraction
- purge block required
- no oozing of inactive material
- clone: unreliable
★★★★★ (clone)
Cyclops NF 2-in-1
- simple setup
- low cost
- non-mixing
- single nozzle
- single heatblock
- single heatsink
- complex retraction
- no oozing of inactive material
- moderate reliability
★★★★★
Diamond Hotend 3-in-1
- complex setup
- clone: low cost
- original: high cost
- mixing
- single nozzle
- single heatblock
- 3 heatsinks
- tricky retraction
- purge block required
- no oozing of inactive material
- moderate reliability
★★★★★
Multiple Switching Extrusions (MSE) 2-in-2, 3-in-3, 4-in-4
- moderate complex setup
- requires additional servo or motor
- extendable 2, 3, or 4 colors/materials
- low cost
- non-mixing
- multiple nozzles / heatblocks / heatsinks
- normal retraction
- no purge block 1)
- no oozing of inactive material
- no inactive nozzle touching print
- reliable 2)
(rating comes later)
Y Splitter x-in-1
- simple setup
- extendable 2, 3, or 4 or more colors / materials
- low cost
- non-mixing
- single nozzle
- single heatblock
- single heatsink
- complex retraction
- purge block required
- no oozing of inactive material
- moderate reliability
★★★★★
Tool Changer
- complex setup
- extendable to n-colors or materials
- moderate cost
- non-mixing
- multiple nozzles / heatblocks / heatsinks
- normal retraction
- no oozing of inactive material
- no inactive nozzle touching print
- moderate reliability
(rating comes later)
Footnotes
- in theory no purge block, but if ooze shields are shared among switching extrusions (more than 2 extrusions) there may be cross-contamination between colors/materials
- the printheads individually are proven to be reliable
Hints:
- single heatblock = same print temperature
- dual heatblock = different print temperatures possible
- dual nozzle = different nozzle sizes possible
That’s it.