What is the EXTRUDER On a 3D Printer? – Why it’s Critical

What is the extruder on a 3D printer? It’s one of the most important pieces of your 3D printer. Without it, you will not be able to create any 3D prints.

In this post, we’ll discuss the role the 3D printer extruder plays in certain additive manufacturing procedures.

what is the extruder on a 3D printer?

One of the most important parts of a 3D printer is the extruder.
One of the most important parts of a 3D printer is the extruder.

An extruder is critical to your additive manufacturing projects as it is the component of your 3D printer that discharges liquid or semi-liquid material in successive layers.

In some situations, the extruder merely uses a bonding agent to solidify a substance that is originally in powder form.

Different 3D Printing Technologies

SLA Printers

In the case of stereolithography (SLA), raw materials are sent to a heated extruder that works in tandem with 3D Filament Deposition Extruders, distributing molten material across a melting pool.

The extruder is required for the effective operation of machines that utilize Binder Jetting, Polyjet technologies, and even 3D Systems’ CPX systems.

These are additive manufacturing machines that require the deposition of substance before changing its chemical properties (Binder Jetting).

Read our related article on the Best SLA 3D Printer on the market! Here are our favorite picks and why.

FDM printers

The component that extrudes liquid plastic and deposits it on a printing platform in an FDM printer is the filament extruder.

A motor drives the plastic filament while a nozzle (or extruder) controls its flow, and adds successive layers to the printing platform.

As technology advances, two extruders are now standard on some types of FDM 3D printers, allowing you to make two materials at the same time.

This advancement allows you to print in two colors and print support material as your project progress that can be extracted by using a solvent.

Some 3D printers, on the other hand, are enclosed to regulate the plastic cooling procedure.

This helps guarantee a consistent temperature in the manufacturing chamber, resulting in more uniform print results.

Binder Jetting Printers

The most prevalent Binder Jetting printers are most likely 3D Systems’ Project models.

An extruder in this printer projects a bonding agent (or color) onto a powdered substance.

It is the act of projecting this bonding agent on successive layers of powder that results in a 3D object.

Polyjet Printers

Up until recently, Polyjet technology was based on the projection of resin droplets onto a printing platform where the resin is UV polymerized after the droplets are projected.

Cold end and hot End Extruders

The extruder is made up of the hot end and the cold end.
The extruder is made up of the hot end and the cold end.

The cold end is located at the upper part of the 3D printer extruder. At this point, the filament is not being heated and is a crucial element of the 3D printer.

The cold end mixes the melted plastic from the hot end with filament from the spool, pushing it into the tube that runs through the printer.

Different systems do exist, however, they are often made up of gears and hobbed bolts, defining how far the printing filament moves.

The printing process then begins with the extrusion of solid material onto the build plate, which is then heated and melted.

The temperature difference between the hot end, cold filament, and the final cold and solid portion must be closely controlled.

The heat break, in tandem with the heat sink, forms a barrier at which the filament is exposed to high temperatures.

This is done through a heater cartridge that is warm, passing heat to the nozzle via the aluminum heater block

The 3D printer nozzle size found on desktop 3D printers is generally 0.4mm, but there are many more to choose from.

The most popular type of nozzle for 3D printers is made of brass but there are a variety of alternatives available with stainless steel being preferable for certain materials.

Direct or Bowden extruder: Which one to choose

When choosing an extruder, there are a few factors to keep in mind when choosing the right one for your project.

Some factors to consider include the type of 3D printer you have, materials you plan to use, printing speed needs, and accuracy desired.

There are two different types of extruders to choose from, Direct and Bowden, but the type of extruder you will need depends on the nature of your job.

All printers feature motors, but geared extruders may be used to regulate printing speed.

It’s not necessary, but it might assist you in customizing your configurations to improve print quality.

Bowden Extruders

A Bowden extruder has a tube that connects the hot end to the extruder body.

The gear then turns by a stepper motor attached directly to the filament feed, allowing for shorter filament paths. 

Direct Extruders

Direct extruders are preferable for 3D printing using flexible filaments because they have a shorter filament path and can be produced entirely with a Direct extruder.

Because only the printing head moves instead of the entire extruder hot end, Bowden extruders can produce quicker models as they are simpler to speed up or slow down.

Both extruders have a direct-drive mechanism and the filament drive technology for either extruder option can be placed on the motor shaft directly.

Additionally, keep in mind that there are extruders for all filament thicknesses, including 3mm filament, 1.75mm filament, and so on.

No matter what type of extruder you choose, you will want to calibrate your extruder to avoid some common issues (discussed below).

The following video illustrates why and how you will want to calibrate your extruder:

Common Issues With Extruders

Three tough printing problems with extruders are:

  1. Bad maintenance
  2. Using the incorrect materials that can cause deterioration or clogging of the nozzle that dispenses the material
  3. Improper cleaning

The main difficulty with 3D printers is that blocked print nozzles prevent the hardened plastic from exiting the extruder, as well as insufficient or misshapen filament extrusion axes.