After a month with 50 g of alumina in each box:
| 2026-10-13 | ||||
| Filament | %RH | Weight – g | Wt gain – g | Gain % |
| PETG-CF Black | 21 | 53.1 | 3.1 | 6.2% |
| PETG White | 23 | 52.6 | 2.6 | 5.2% |
| PETG Black | 23 | 53.2 | 3.2 | 6.4% |
| TPU Black | 24 | 52.8 | 2.8 | 5.6% |
| PETG Orange | 27 | 52.9 | 2.9 | 5.8% |
| PETG-CF Gray | 30 | 53.3 | 3.3 | 6.6% |
| TPU Clear | 31 | 52.9 | 2.9 | 5.8% |
| PETG Clear | 33 | 53.3 | 3.3 | 6.6% |
| PETG-CF Blue | 30 | 53.7 | 3.7 | 7.4% |
| PETG Blue | 25 | 53.0 | 3.0 | 6.0% |
A day later, most of the boxes were in the 10%RH to 15%RH range, with the filament spools slowly releasing their stored moisture. The PETG Orange meter jumps between 10% and 27%, with the latter more believeable.
Changing the desiccant every month, without thinking too hard, may be the simplest path to dry filament storage.
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