FreeDirect drive dual extruder (single-nozzle and single-drive)
Thingiverse
32 model
Free
FreeBowden dual/quad extrusion extruder (single-nozzle single-drive) + video
Thingiverse
FreeCompact Prusa i3 E3D V6 Dual or single Extruder V2
Thingiverse
FreeLightweight Dual to Single Extruder Conversion with Active Cooler for CTC / Flashforge
Thingiverse
FreeEnder 3 V2, direct drive adapter for Metal Extruder single drive
Thingiverse
FreeFang (fan) Duct for Tevo Tarantula Single Extruder Stock
Thingiverse
FreeFlashForge Creator Pro left single extruder fan duct
Thingiverse
FreeUniversal X Carriage for single and double extruder Prusa i3 Sunhokey
Thingiverse
FreeHTA3D Single Extruder - optimized for flexible filament - Mk8 and V6
Thingiverse
FreeGeeetech Prusa I3 Pro B Single Bowden extruder holder for E3D V6 or clone
Thingiverse
FreeThe nOrbiter V1.5 Single stage gearbox dual drive extruder
Thingiverse
FreeD.E.I.S.S. Dual Extruder Interfacing Single Stepper (Robo3D)
Thingiverse
FreeIqos Ashtray for Single Extruder
Thingiverse
FreeHow to multi color print on single extruder (Ender 3 + Cura)
Thingiverse
FreeE3D Dual/Single direct drive extruder conversion for Felix Printer
Thingiverse
FreeBowden dual/quad extrusion extruder (single-nozzle single-drive) for MG995 SERVO
Thingiverse
FreeTevo Tarantula Fang Fan Single Extruder w/ BLTouch support
Thingiverse
FreeTevo Tarantula Dual Blower/Radial Fan Duct for Single/Chimera dual extruder + various BLTouch supports
Thingiverse
FreeCR 10 Direct Drive Extruder Mod Single Part
Thingiverse
FreeDead Simple Inlay Technique (single extruder, no GCODE hacking)
Thingiverse
FreeMakergear M2 Single V4 Extruder Fan Shroud
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FreeAnet A8 Dual Extruder Motor Holder (single/dual-color)
Thingiverse
FreeFanduct for Geeetech Prusa i3 Pro B, single MK8 extruder, 40mm fan
Thingiverse
Freexc3dmaker 3D Printer J-head Hotend with Single Cooling Fan for 1.75mm/3.0mm E3D v6 Direct Filament maker Extruder 0.4mm Nozzle
Thingiverse
FreeRigidbot Easy Print Cooling Fan Mount for Single Extruder
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FreeFan Duct for Raise 3D N2/N2+, Single Extruder
Thingiverse
Free20MM x.4MM Single Wall Extruder Calibration Cube
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FreeHybrid Dual Color Single Hot End Extruder
Thingiverse
FreeSingle Extruder conversion for CTC
Thingiverse
FreeTevo Tarantula Single Extruder 30mm to 40mm fan adapter + Dual blower mount
Thingiverse
FreeDual to Single Extruder for Flashforge Creator Pro
Thingiverse
FreeGEEETech i3B (METAL version): Single Extruder FAN & LED (V3 with 3DTouch)
Thingiverse