Filament diameter is the most underrated spec in 3D printing. A filament that drifts between 1.70 and 1.80 mm causes under-extrusion, jams, weak layers and ugly surfaces — even on a perfectly tuned printer.
1.75 mm is the standard
Nearly all modern printers (Bambu Lab, Prusa, Creality, Voron, Anycubic, Elegoo) use 1.75 mm filament. The slicer assumes a constant cross-section; any deviation changes the actual extrusion volume.
Tolerance: ±0.02 mm vs ±0.05 mm
| Tolerance | What it means | Who offers it |
|---|---|---|
| ±0.02 mm | Premium: consistent flow, reliable long prints | Top brands (incl. VOXFIL, measured inline 24/7) |
| ±0.03–0.05 mm | Budget: visible variation, more calibration needed | Many budget imports |
How to measure it yourself
Use a digital caliper: measure 10 points, rotate 90° at each, note min/max and roundness. If variance exceeds 0.05 mm across a spool, you'll see it in prints.
What to demand from a supplier
- Tolerance in writing (not just marketing)
- Inline laser gauging (continuous) vs spot checks
- Batch reports with real measurements
VOXFIL measures every meter with inline lasers and publishes the process publicly — ±0.02 mm isn't a claim, it's a measurement.