Loading pellets
How to load pellets into the G1 hopper correctly, including pre-checks and material mixing guidelines. Doing this wrong causes feeding problems and poor print quality.
When to do it
Section titled “When to do it”- Before every print session
- When the hopper runs empty mid-print
- When switching materials (do a Material change and purge first)
Prerequisites
Section titled “Prerequisites”- Pellets dried if using hygroscopic materials (PETG, rPLA, PCTG) — see Dryer best practices
- Vacuum pump connected and powered (feeding socket on the power box — see Power outlets (power box))
- Corrugated tube connected and clamped at both ends — see Corrugated tube
1 — Check pellet condition
Section titled “1 — Check pellet condition”Before loading, inspect the pellets:
- Moisture: if you hear crackle during extrusion or see foam → dry first
- Powder contamination: fine powder and small crumbles (common in recycled or ground materials) accumulate at the hopper entrance and block flow → see Mixing tip below
- Pellet size: very large or irregular pellets may jam; reduce print speed to allow complete melting
- Aggregation: if pellets are stuck together in clumps (dryer too hot) → discard and use fresh material — see Dryer best practices
2 — Fill the pellet bucket
Section titled “2 — Fill the pellet bucket”- Pour pellets into the pellet bucket (the external container connected to the corrugated tube)
- Leave the lid slightly open or ventilated — a fully sealed container can collapse from suction
- Keep the bucket close to the machine — maximum ~1.5 m tube length
3 — Prime the vacuum
Section titled “3 — Prime the vacuum”- Power on the printer
- The vacuum pump should activate automatically and transport pellets to the hopper
- Watch the hopper through the top — pellets should be visible within 1–2 minutes
- If suction is weak or no pellets arrive → see Hopper suction problems
4 — Verify before printing
Section titled “4 — Verify before printing”- The hopper should be at least half full before starting a long print
- Check that pellets are freely flowing (not bridging at the hopper neck)
- If using Liquid Masterbatch: verify it is loaded in the dosing pump before starting
Mixing guidelines for recycled / ground materials
Section titled “Mixing guidelines for recycled / ground materials”If printing with recycled pellets that contain fine powder or irregular sizes:
- Mix 50% recycled + 50% virgin material as a starting point
- Pure recycled (especially ground/shredded material) tends to form powder bridges at the hopper entrance, blocking flow
- If clogging persists, increase the virgin material proportion to 60–70%
Liquid Masterbatch loading
Section titled “Liquid Masterbatch loading”If using Liquid Masterbatch for color:
- Use a maximum of 1 g per 2 kg material (0.05% ratio)
- The dosing pump draws from a small bottle — check bottle level before starting
- Reduce mixing stepper Rotation Volume by ~10–20% when using liquid masterbatch (the added liquid increases apparent flow)
Common mistakes
Section titled “Common mistakes”| Mistake | Effect | Fix |
|---|---|---|
| Loading wet pellets | Foaming, bubbles, weak layers | Dry first at 65°C for 3–5 h |
| Too much recycled powder | Hopper bridging / no flow | Mix 50% virgin material |
| Bucket too far from machine | Weak suction, pellets don’t arrive | Shorten tube to < 1.5 m |
| Tube not clamped | Air leak reduces suction | Clamp both ends tightly |
| Aggregated pellets loaded | Motor jamming | Discard aggregated material |
Final verification
Section titled “Final verification”Hopper is at least half full, pellets are loose and freely flowing, no clumping visible at the hopper neck. Extrude a short purge line before starting — it should be smooth, consistent, and free of bubbles.