Hemera XS



  • Be aware of your electronics. Please don't work on your printer while it's turned on. We advise disconnecting from the mains during installation and maintenance.
  • During use and cooldown, there is a potential to burn your hands.
  • Please read and make sure you understand the firmware requirements before attempting to print.
  • Please check that the components' voltage matches your printer's voltage. Double-check the polarity of connections where appropriate.
  • Your HotEnd and printer are your responsibility. We cannot be held responsible for damages caused by our products use, misuse or abuse.


  • Drive Type: dual drive with adjustable tension idler
  • Max Printing Temperature: 300°C
  • Nominal steps per mm (x16): 397
  • Recommended current: 1.4A Peak (~0.99 RMS)
  • Filament diameter: 1.75mm

Note: Your own 3D Printer setup and filament choice will have an effect on the maximum VFR you can achieve so bear this in mind when referring to these values.

Volumes & Dimensions

Weight: 256.25g

Performance Characteristics

  • Maximum printing temperature: 300°C

Service Temperatures

Note, these are max ambient service temperatures of the components used, and not a guaranteed operating temperature of the system

  • Fan: 50°C
  • Motor: 85°C
  • Polymer bushing: 90°C
  • Bearings: 100°C
  • Acetal idler components: 120°C

Power Vs Temperature (Direct or with Revo HotEnd)

Initial Resistance of a 24V heater at 23°C: 14.4Ω
Temp Coefficient of HeaterCore: 0.002078
Temp Coefficient of Heater Cartridge: 0.002078

Mounting Guidance

Hemera is mounted to a flat surface via the T-slots on the left or right sides of the motor. Typically Hemera is mounted onto the left side, as the air from the heatsink cooling fan exits on the right. If mounting on the right, ensure that sufficient space is left for airflow.

The screws must protrude 3mm±0.25mm from the mounting surface to go into the T-slots. The supplied M3×8 mounting screws are suitable for a nominal 5mm mounting plate thickness. Hemera must be mounted on a minimum of 2 mounting points, if using 2 mounting points, diagonally opposing points should be used, in order to ensure rigidity.


  • Fan: Dupont 0.1”
  • Heater: Molex Micro-Fit 3.0, 2 pin horizontal
  • Temperature sensor: Molex Micro-Fit 3.0, 2 pin horizontal
  • Assembly is supplied with 1m cables to connect to mainboard

Fan Specification (Direct)

  • Width: 40mm
  • Depth: 10mm
  • Cable: 1000mm
  • Voltage: 12VDC and 24VDC
  • Current: 0.08A (12V) and 0.04A (24V)
  • RPMS: 7500±10% (12V) and 6900±10% (24V)
  • Speed: 7000RPM
  • Connector: Dupont 0.1”
  • Startup voltage: 6 VDC (12V) and 12VDC (24V)Airflow: 6.8 CFM
  • Static Pressure: 4.55 mmH20
  • Noise level: 33.6 dBA
  • Weight: 14g

Motor Specification & Diagrams

  • Motor cable length: 1000mm
  • Phase no: 2 phases
  • Rated voltage per phase: 3.22V
  • Recommended Current: 1.40A Peak (~0.99A RMS)
  • Resistance: 2.3Ω per phase
  • Inductance: 2.5mH
  • Holding torque: 180mNm
  • Detent torque: 10mNm
  • Rotate direction: ABĀB̅ CW
  • Insulation class: Class B
  • Rotor inertia: 24.3gcm²
  • Connector: JST - 56B - PH
  • Step angle: 1.8°
  • Motor mass: 160g


  • Do not remove the grease from the drive gears.
  • Compressed air is a recommended method of dislodging filament debris from hobb teeth.
  • Avoid using wire brushes on the hobb teeth or gears.


  • Heatsink: die cast aluminium (Direct)
  • Extruder cover: MJF Nylon (Bowden)
  • Gear/Hobb materials: stainless steel
  • Fixings: steel
  • Idler materials: Acetal
  • Bearing elements: 2x shielded 623 bearings (drive shaft), Igus bushing.

Note: Your own 3D Printer setup and filament choice will have an effect on the maximum VFR you can achieve so bear this in mind when referring to these values.

Exploded View

  • Self-Tapping screws
  • 4010 fan
  • Revo spring
  • Revo HeaterCore
  • Revo HeaterCore sock
  • Revo Nozzle
  • Revo Nozzle sock
  • Hemera XS