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FM Essentials: The Heaters

Collected information explaining the function and features of the Filament Maker Heaters. These essentials are to help you understand how best to use the machine to your specifications.

The Filament Maker extrudes with a collection of features and components working together efficiently. It is up to the user to utilize these tools and ensure that the machine works well.


Table of Contents

Things to Watch Out For
Machine Settings
Safety / Error Messages
Further Information


After the material enters the Filament Maker through the Hopper, and is pushed forward by the Screw, it’s time for the Heaters to do their part. Heat is applied from four heaters around the outside of the barrel. Heaters are labelled H4, H3, H2, and H1 from Hopper to Nozzle.

Along with the Heaters, material melting is caused by friction, too.


The material’s time in the barrel can be segmented into 3 zones that are responsible for the state of the matter.

1. Feeding

Closest to the Hopper, Heaters 4 and 3 are responsible for starting the melting process. As explained in the Hopper Essentials, there must be solid material early in the barrel to help push material forward.

2. Transitioning

In the middle of the barrel, Heaters 3 and 2 help transition the material into a fully melted state. Also known as the compression zone, this is where the material turns homogenous. Past Heater 2, the material should be fully melted.

3. Metering

Closest to the nozzle, the now liquid material is regulated and kept molten by Heaters 2 and 1. This zone is most responsible for the texture of the output. The stable flow is ready to extrude through the Nozzle.


Heater Sections


The knowledge of the zones is essential as it helps troubleshoot the extrusion process. Here are some examples in very general terms:

If the output is very liquid but the pressure is good?    ->   Lower H2 and/or H1

If the pressure is stable, but the texture is too rough?   ->   Raise H2 and/or H1

If the pressure is weak, but output texture is good?      ->  Lower H4 and/or H3


Each heater has a thermocouple attached to it, which measures the temperature of each Heater and therefore the approximate temperature of the material in the barrel. These are the temperatures to set and adjust in the Machine Settings.

Heat Transfer

The Heaters are insulated and can be set separately. However, if there are extreme temperature differences between two adjacent Heaters (30+ Celsius), they will affect each other. This is normal as heat transfers through the barrel.

Things to Watch out for


The Heaters are quick to heat up and slow at cooling down. Take that into consideration when using the machine and especially when changing the settings.

Heater 1

For various reasons, Heater 1 is the slowest to heat up.

Heater 4

Heater 4 is the one closest to the Hopper and even though it is insulated, it is good to watch out for any early melting near the Feeding zone (point 3) when using high temperatures.

Material Temperature

It is important to know that the temperature of the Heaters is not always the same as the temperature of the material travelling inside the machine, because...

...some polymers take a long time to heat up and cool down.

...some polymers are prone to early melting.

...some polymers are quick to solidify when exiting the nozzle.

It’s essential that you become familiar with the material you are extruding and use the Heaters to manipulate and process the material effectively.


If the Heaters are at their set temperatures, the material must be moving!

As mentioned before, polymers pick up and store heat. If the material is idle in the barrel, it will get hotter and hotter, and will start to degrade over time and maybe start to burn. This can happen even if the Heater temperatures are set within the safe range of the polymer.

No Empty Barrel

The barrel is never empty!

Even if material in the Hopper runs out, and there is no extruding material, there will always be residue and bits of material flowing around in the barrel. This is incredibly bad for the machine, as the Heaters will continue to degrade the left-over material.

Make sure there is always DevoClean MidTemp (purging material) or a moving Filament material in the Hopper!

Machine Settings

Heaters: 1, 2, 3, 4

0* – 450 C

*When the machine is off, the Heaters are at the Room Temperature, not 0.

Safety / Error Messages

Safety Warnings:

Since the Heaters are inside the machine, they pose little direct danger.

However, due to working with extreme temperatures and potentially degrading polymers, harmful fumes may be a side effect of using the Filament Maker. Please thoroughly research your materials, and prepare an environment that is well ventilated!

Error Messages:

Most common Error Message related to the Heaters is "Failure Reading a Thermocouple".

Further Information

Here's a step by step practical guide on how to replace a Heater.

Tips on diagnosing a faulty Heater, including possible causes and solutions.

Troubleshooting output that is too liquid, and how to fix it.

Next essential: The Nozzle