Filament spool drying insert

A silica gel container which fits in the spool center. Made specifically for BambuLab reusable spools but can fit others as well.

If your spool has the same (or larger) center hole dimensions it will work.

It will keep your filament dry when stored in resealable bags or significantly improve AMS humidity levels.

It holds a lot of silica gel and last for a long time.

Make it with appropriate material so it won't deform when drying at higher temperatures.

I recommend PETG, ABS or ASA. For higher drying temperatures, ASA should be used.

Advantages

Easy to use - only two parts are required and can fit loose or packaged silica beads.
Easy to make - simple geometry can be made without supports on any 3D printer.
Large volume - internal volume is 110mL meaning it will hold a lot of silica gel.
High perforation - very effective at absorbing humidity.
Open design - sides don't touch the spool so the humidity can be absorbed throughout the whole model, maximizing the effectiveness.
Compatible with smaller loose silica gel - even the smaller 2mm size silica gel beads can be used without issues.

Use

To use the model, print both parts.

Fill the larger part with silica gel as much as you want. Alternatively, you can use silica gel packages and stuff as much as you can in the container.

Simply place the cap on top.

If you use loose beads I recommend you glue the cap. A few drops of superglue is all you need. Alternatively, you can use tape with sufficient temperature resistance to hold the cap in place (kapton / polyimide tape).

Insert the assembled part in to the spool center hole.

You can secure the container to the spool with a few pieces of tape so it won't fall out.

That is it, enjoy your dry filament when you store it in a resealable bag.

If you use a non BambuLab spool the hole may be too big. In this case you can print a simple ring to act as an adapter or use tape on both ends of the spool.

Update 24.1.2026

The cap should be glued in place, either with superglue (permanent) or tape (removable). This is mentioned originally above as well and the text was now made bold for better visibility.

Descrição

Advantages

Use