People keep asking whether they need a dryer or a dry box, so here is what I learned from tracking humidity in my setup for about 2 months.
Context: my room sits around 65% RH most of the year. I have a P2S with AMS 2, about 15 spools in rotation and 40 total.
The short version:
- A dryer fixes a wet spool right now. That is a one-time operation.
- A dry box or cabinet keeps your spools dry over time. That is the permanent fix.
- You need both. They do different jobs.
What I actually tracked:
- After a 6-hour dry cycle, a spool left on the open shelf reabsorbed moisture within about 2 days back to where it started.
- Spools in small sealed boxes with desiccant stayed around 30% RH for weeks.
- After moving everything into one bigger cabinet with molecular sieve desiccant, it holds around 25% RH consistently, and I check the desiccant maybe once a month.
The lesson for AMS owners: your AMS protects 4 spools. The other 36 are on you. Drying the 4 in rotation is not enough if the rest of your collection is slowly turning into sponges.
If you are deciding between a dryer and a cabinet, they are not competing tools. A dryer rescues wet filament. A cabinet stops the problem from happening in the first place.
Happy to answer questions. Also, if your room RH is high, check your desiccant more often than you think you need to.