Complete drybox solution using IKEA 365+ food storage container 10,6 L
This is a remix from this projet create by crashdebug.

improvements

The problem with the metal PTFE (teflon) holder and the angle of the outlet outside : This generates friction.
I use a 60cm PTFE tube from the drybox connected to the direct drive printer (flsun v400). Long but no friction if the tube is put inside the dry box. Need to put a little piece of tube after usage.
I redesign the outlet.

dry container

I've design a dry container that feet the shape of the box and the spools.
You can use silicate cat litter, this is the same product as the amazon marbles but raw and cheaper. 1 bag of 2kg is enough for 7 containers.
Let it for 4-5hours in a oven at 60° to dry them and put to the ikea dry container

hygrometer

The hygrometer is inside with double face tape (zigbee device to monitor in my case). Less screw and holes. Feel free to use the original hygrometer holder if needed.

The parts are designed for standard spools hub diameter :

• 54mm
• 55mm
• 57mm carboard form futura
• 60mm azurfilm
• 75mm geektech TPU

Hint: It works best to screw on the quick release fittings while the part is still hot and soft. Otherwise it might be necessary to cut an M6 thread.

Spool size:
The spools shown in the picture have about 65mm width and 200mm diameter. The hub is 54mm diameter on one side and 55mm on the other. I believe this is the most common spool size I have seen. If your spool is significantly larger than that, it will likely not fit in the container.

Hardware needed:
1 box ikea 365+
1 lid ikea 365+
16x M3x10 (or longer) bolts
16x M3 nut
1x M8 threaded rod for spools (length 172mm when fixed midway of box height)
2x M8 nuts and some washers as spacers between spools
2x Teflon tubes
1x zigbee hygrometer (2xAA batteries) for less than 5€ here or 3€ here or Cheap amazon hygrometer (see picture)

Print:
2x outlet inside
2x outlet outside
2x roller mount inside
2x roller mount outside
4x roller hub 54mm or other size
1x ikea dehydratation

Total cost per dry box is 15€ for 2 spools.

Tips : you can reuse this for another cheaper ikea box for 4 spools, but you need to add a seal on the box yourself, with TPU for example