A 3D printer extruder is a filament feeding mechanism used in many

fused filament fabrication Fused filament fabrication (FFF), also known as fused deposition modeling (with the trademarked acronym FDM), or called ''filament freeform fabrication'', is a 3D printing process that uses a continuous filament of a thermoplastic material. Filam ...

(FFF)

3D printer 3D printing or additive manufacturing is the construction of a three-dimensional object from a CAD model or a digital 3D model. It can be done in a variety of processes in which material is deposited, joined or solidified under computer co ...

s. There are several types of 3D printer extruders. A

Bowden Bowden may refer to: Places Australia * Bowden Island, one of the Family Islands in Queensland * Bowden, South Australia, northwestern suburb of Adelaide * Bowden railway station Canada * Bowden, Alberta, town in central Alberta England * Bowde ...

extruder is a type of extruder that pushes filament though a long and flexible PTFE (Teflon) tube to the hot end. An alternative type of extruder which is also widely used in filament 3D printers is the

direct-drive A direct-drive mechanism is a mechanism design where the force or torque from a prime mover is transmitted directly to the effector device (such as the drive wheels of a vehicle) without involving any intermediate couplings such as a gear train o ...

extruder, which sits closer to the extruder hot end.

Bowden extruder

Bowden type extruders are easier to swap since they are outside the print head. They also have less chance of tangling the filament while it unwinds from the spool. Additionally, they reduce the

mass Mass is an intrinsic property of a body. It was traditionally believed to be related to the quantity of matter in a physical body, until the discovery of the atom and particle physics. It was found that different atoms and different eleme ...

of the extrusion carriage because it doesn't have to hold a

stepper motor A stepper motor, also known as step motor or stepping motor, is a brushless DC electric motor that divides a full rotation into a number of equal steps. The motor's position can be commanded to move and hold at one of these steps without any posi ...

. This allows for faster changes in print head movement direction, increased print speed, increased accuracy, and decreased instances of artifacting or ghosting along the x and y axes. One disadvantage is that because Bowden extruders push filament through a long and curved tube, more friction must be overcome compared with direct drive extruders. To partially mitigate these friction forces, the tube is made of PTFE, which has a low coefficient of friction. Flexible filaments do not print well because the filament flexes inside the tube and clogs up the machine. Another disadvantage is that the feeding distance is relatively long, and thus the resistance is high, meaning the stepping motor of extrusion is required to have a higher torque.

Direct-drive extruder

With a direct-drive extruder, the motor pushing the filament is installed by the hotend and pushes the filament directly into the nozzle. Direct-drive designs have several advantages, and typically give better extrusion, faster retraction, are able to print more types of filaments, and can use a smaller and lighter motor due to the short distance to the nozzle. One typical disadvantage of direct-drive extruders is the added mass to the hotend, compared to a typical Bowden extruder, which may cause more vibrations so that the direct-drive printhead has to move slower, which can affect print speed. Another typical disadvantage is more complex maintenanceDirect-drive extruder vs. Bowden extruder - Guide - 3DJake International
/ref> due to tight packaging of many components in the hotend.

References

{{DEFAULTSORT:3D printer extruder Fused filament fabrication 3D printing

Bowden extruder

Direct-drive extruder

See also

References