Filament Heads

Filament heads are how we print (using FFF or FDM) with filament-based materials which are deposited at over 150°C, depending on the head.

Note that at present, our Filament heads work with 1.75mm filament (actually, 1.6mm to 1.9mm), but not 3mm filament.

Materials for Filament Heads

The following materials can be printed from Filament heads.

• ABS (Acrylonitrile Butadiene Styrene)
  • Flame Retardant ABS
  • ABS - PC Alloy
  • Conductive ABS
  • Smart ABS
• BendLay
• Flex 45
• HIPS (High-Impact PolyStyrene)
• LayBrick
• LayWoo-d3
• MoldLay
• Ninjaflex
• Nylon
  • Taulman 618, 645, 910
• PC (PolyCarbnoate)
• PEI (PolyEtherImide) - AKA Ultem
• PEEK (PolyEther Ether Ketone)
• PET (PolyEthylene Terephthalate)
• PETG PolyEthylene Terephthalate Glycol-modified)
• PLA (PolyLactic Acid)
  • EcoFlex PLA
  • Conductive PLA
  • SS PLA (Stainless Steel infused)
• PlastInk_Rubber
• PP (PolyPropylene)
• PVA (PolyVinyl Alcohol)
• T-Glase
• Ultem

Filament Heads

Filament-based printing is available through the following heads:

• 

  FH2-260

• 

  FH2-450

Discontinued heads:

• 

  HT3-260

• 

  HT3-450

• 

  MK1-250

• 

  MK2-250

• 

  MK1-450

1. General Filament Head Videos:
   1. MK Series Printing Tips
   2. Post Processing with a Heat Gun
   3. Loading and Unloading Filament in the MK Series head
2. MK1-250 Extruder for Standard Filament Videos:
   1. Overview
   2. Loading and Printing
3. MK2-250 Extruder for Flexible Filament Videos:
   1. Overview
   2. Loading and Printing
4. MK1-450 Extruder for High-Temperature Filament Videos:
   1. Overview
   2. Loading and Printing

Please see our Data Sheets as well.

Table of Filament Heads

The following table compares the properties of the various Filament heads, including which heads are recommended for which materials. The MK1 heads drive material from one side, with a spring-loaded bearing system to maintain pressure and positioning. The MK2 heads drive the material from both sides, and are designed for more flexible filaments.

Filament Head Properties

Head	Min Temp	Max Temp	Filament Type	Filament Size in mm	Nozzle Type	Nozzle Sizes in mm	Recommended For	Description
FH2-260 high torque	150°C	250°C * 265°C	Standard	1.75 +/- 0.15	E3D v6 compatible	standard options	ABS, HIPS, LayBrick, LayWood, Nylon, PC, PET, PETG, PETT, PLA, PP, PVA, T-Glase	High Torque for Standard 1.75mm Filaments
FH2-450 high torque	275°C	450°C	Engineering	1.75 +/- 0.15	E3D v6 or MK8 compatible	standard options	PEEK, PEI (Ultem), PEKK, PPSU	High Torque for High Temperature 1.75mm Filaments
HT3-260 high torque	150°C	250°C * 265°C	Standard	2.85 +/- 0.15	E3D v6 compatible 3 mm bore	standard options	ABS, HIPS, LayBrick, LayWood, Nylon, PC, PET, PETG, PETT, PLA, PP, PVA, T-Glase	High Torque for Standard 2.85mm Filaments
HT3-450 high torque	275°C	450°C	Engineering	2.85 +/- 0.15	E3D v6 or MK8 compatible 3 mm bore	standard options	PEEK, PEI (Ultem), PEKK, PPSU	High Torque for High Temperature 2.85mm Filaments

Research Papers Citing Hyrel Filament

These are now listed by year here.

Firmware Versions for Filament Heads

Firmware information is listed on our Firmware page.

How do I change nozzles or clean nozzles?

Carefully:

1. Heat to the printing temperature of the material loaded.
2. Move the manual lever to the left, retracting material until it is free of the advancement gear, then remove by hand.
3. Turn off heat to the head and remove it from the yoke. *Nozzle should be HOT when this step is done; use caution.
4. With a 1/4" driver or wrench, remove the nozzle.
5. Inspect the nozzle cavity for any stray material; if found, remove with tweezers, solvent, air pressure or other means.
6. The old nozzle can be cleaned with a fine drill bit the same size as (or slightly smaller than) the nozzle diameter; some users also soak the nozzle in an appropriate solvent to remove all material.
7. With a 1/4" driver or wrench, attach the new nozzle.
8. Use normal procedure for heating and loading filament.

How do I change nozzle sizes?

There are two places where we consider nozzle size:

1. On the head, we use the number you have for nozzle diameter to make our flow calculations. See Flow Rate for details about how we determine how fast to spin the motor so that you get the proper volume per second of deposition. This image is for printing with a 14# (fourteen gauge, or 1.6mm ID) luer needle:

2. In the recipe, we use the extrusion width numbers to determine how far apart to place each bead of material. We expect your extrusion width to be 10% wider than your nozzle diameter (to allow for a nice sandbag-shaped cross section). This image is for printing with a 14# (fourteen gauge, or 1.6mm ID) luer needle:

This applies to everything we print, from PLA to Porcelain to PEEK.

Please note that we do NOT use any other variable relating to nozzle diameter. Not Bridge Flow Ratio. Not Nozzle Diameter. Not Extrusion Multiplier. All of these variables affect the E values in your gcode. Which we then ignore.

How do I load an Extruder onto the Printer

As with all Hyrel heads, the following process should be followed:

1. Start with a level bed and Repetrel running and connected to the printer.
2. Load the gibs on the Head into the gib slots on the Yoke from above and slide the head down into place; the last mm of travel should be done gently, ensuring that the electrical connector seats properly (firmly and completely) into the receiving connector.
3. Ensure the LEDs on the print head are flashing - this means the Head is communicating with the Motion Controller.
4. Tighten the thumbscrew in the rear, to prevent the head from moving relative to the Yoke.
5. If the Head doesn't show up in Repetrel, press and release the RESET button on the front of the printer.
6. Once the Head is shown in repetrel, proceed to setting your Z-Zero position.

See also: Loading Print Heads into your Hyrel 3D Printer

How do I load material into a Filament Head?

Filament heads all ship with a remaining piece of filament from the last test print (ABS, 240C for low-temp heads, and PEEK, 420C for high-temp heads. We recommend leaving a few cm of filament above the head when changing heads.

Unloading:

1. With the head properly seated and the emergency stop OUT, warm the head to the service temperature of the presently loaded material.
2. If presently loaded to a spool, press down on the blue pneumatic fitting and release the guide tubing; then cut the filament a few cm above the head.
3. Press the manual feed lever (at the top left of the head's 103 circuit board) to the left, retracting the filament. Retract until the filament comes free of the motor shaft, then remove.

Loading:

1. Straighten (if needed) the last few cm of the new filament, which should be routed through the guide tubing. Insert it down through the pneumatic fitting, into the PTFE guide tube, until it comes in contact with the motor shafts.
2. Press the manual feed lever to the right, advancing the filament two to three cm.
3. In repetrel, click the motor on at 500 (pulses per second) until the new filament advances to the melting zone and forces the old filament out. Advance about 30cm of filament, checking for smooth sides and uniform color.
4. Remove excess filament with tweezers. Seat the guide tubing. You are ready to go.

See also: How to Load Filament into a Hyrel 3D Print Head