The Enderstruder: An accessible open-source syringe extruder compatible with Ender series 3D printers

1. Motion—Motion accuracy: not reported
2. Volume—Volumetric accuracy: not reported
3. Viability—Cell viability: not reported
4. Unattended—Unattended operation: not reported
5. Standard—Standard compliance: not reported

The full text was read and states no figure for any of the five.

Each score is shown against the range the other 59 builds actually occupy, because no criterion uses the full 1–5 scale. These describe how reproducible the build is, not how good the science is.

• Resolution

  4/1–5

  10240 microsteps/mm on a 1.25 mm M8 screw with 4:1 gearing gives ~0.016 uL per microstep through a 27G needle, with filament width variation within 110 µm.

• Throughput

  3/2–5

  One 10 mL BD syringe on a single nozzle handling one ink at a time; prints complete constructs unattended in under an hour but has no parallel channels.

• Parts sourcing

  4/2–4

  Mostly off-the-shelf or kit-based components.

• Skill needed

  2/2–4

  Multiple advanced technical skills appear required.

• Facilities needed

  4/2–4

  Uses common benchtop/desktop equipment or generic consumables.

• Documentation

  4/2–5

  Open resources include several build or operation artifacts.

• Validation effort

  3/2–4

  Five inks tested for filament uniformity, fusion and printability score plus a gravimetric E-step calibration protocol; Table 1 compares only other open designs’ specs, no experimental benchmark.

• Cycle time

  3/1–4

  No timing comparison reported; print speeds of 5-20 mm/s and sub-hour prints are stated but never measured against a commercial extruder or manual method.