filament dry Box with rotating rollers

This 3‑D printable insert converts a GoMaihe 4 L airtight food‑storage container into a sealed, low‑humidity filament feeder. Four rollers on 608 bearings (8 × 22 × 7 mm) support one spool up to 70 mm wide (≈1 kg, Ø200 mm), letting it turn freely while the lid stays closed. A press‑fit ring in the lid takes a round hygrometer/thermometer (Ø45 mm) so you can monitor temperature and humidity without drilling.Key BenefitsConsistently dry printing – The factory gasket plus a desiccant bay beneath the rollers hold relative humidity below 20 % RH, protecting hygroscopic materials such as PA, TPU and PVA.Smooth, low‑friction feed – Four 608‑bearing rollers centre the spool and let it rotate with minimal resistance, preventing tension spikes and tangles.Tool‑free monitoring – The snap‑in hygrometer ring adds environmental sensing with no glue, screws or drilling.Integrated filament pass‑through – A Ø4 mm PTFE‑tube channel preserves the airtight seal while guiding filament directly to the print