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, and fed from the dryer, for PETG and recycled PLA — see Starting the dryer
- 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: pellets stuck together in clumps (dryer ran too hot) → break them apart and check no compacted lump gets through. The material is still good — see Starting the dryer
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 bucket lid vented — a fully sealed container collapses under the suction. This is the feed bucket, not the dryer: the dryer is always run closed
- Keep the run to the machine short and, above all, without dips — see Corrugated tube for the rule that matters, which is the shape of the run rather than its 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:
- 0.05–0.08% by weight is where to start — 0.5 to 0.8 g per kg. How much colour you need depends on the pigment, but stay below 0.1%. See Liquid Masterbatch
- Check the bottle level before starting a long job
- Masterbatch shifts the volume delivered per screw turn, so check the Rotation Volume after dialling in a new colour. Check it by measuring — do not adjust it blind
Common mistakes
Section titled “Common mistakes”| Mistake | Effect | Fix |
|---|---|---|
| Loading wet pellets | Foaming, bubbles, weak layers | Dry first — see Starting the dryer |
| Too much recycled powder | Hopper bridging / no flow | Mix 50% virgin material |
| Tube dips or loops on the way up | Pellets settle in the low point and stop | Re-route so the run climbs — see Corrugated tube |
| Tube not clamped | Air leak reduces suction | Clamp both ends tightly |
| Aggregated pellets loaded | Motor jamming | Break the clumps up before loading, not after |
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.