Desiccant Box 150x60mm

I had a need to control the moisture level in my filament reel ziplock bags and my printer dry box.  Little 3g dessicant bags were insuffcient at keeping the moisture levels low.  So, I purchased bulk Silica Gel to be used to get the moisture levels under control.

My approach was to place a measured amount of Silica Gel into a ziplock bag and dry box.  Loose Silica Gel in a bag was potentially messy.  So, I needed a small box with lots of small holes to capture the Silica Gel into.  I 3D designed a box and filled it with the desiccant.  The box tray size is 150 x 60mm and 20mm high (outside dimensions).  This box hold about 100g of Silica Gel.

This is a second desiccant box I have shared.  The other box is smaller and has an intended capacity of about 70g of Silica Gel.

I found 3 boxes (300g) of Silica Gel keeps my dry box humidity level below 10%.  Since low humidity is essential when working with Nylon filament (other hygroscopic filaments, too), this solution worked well at keeping the Nylon dry whilst in use.

Normal opening and closing of the dry box allows relatively moist air to enter the bag.  So it's a good idea to monitor the humidity level.  Over time, if the desiccant can't keep the humidty low enough, replace the desiccant and dry out the old desiccant ready for re-use.

Similarly for my filament reel ziplock bags.  Over time, the Silica Gel in the ziplock bag will also need refreshing and drying out.

The 3D printed box lid nicely friction fits onto the box.  The risk of the box accidently being knocked open is low, but should it happen, that's a lot of desiccant pieces to get scattered, retrieve and clean up, so I place a rubber band around the filled box.

NOTES
- There are factors that need consideration should you choose to duplicate my results.  These include the normal ambient air humidity level, the Silica Gel effectiveness and how well the Silica Gel has been dried out, to name a few.  If unsure, the simple rule is more Silica Gel will dry remove more moisture from the surrounding air and will not damage the filament.

- This approach to keeping filament dry is effective for filament that is already dry.  Desiccant alone will not remove moisture that has already been absorbed by the filament.  A filament drying process not covered here is required.

- There are alternatives to Silica Gel to remove moisture from the air that can be effective, too.  These alternatives are more or less effective, relative to Silica Gel, hence the quantity placed in this box will need adjusting, accordingly.

Apart from the 3D printed parts, I use a small cut out of fibreglass flyscreen mesh.  Something on hand, but also easily sourced from your hardware store.  The mesh is secured in-place by super glue and sandwiched with a 3D ring to keep the mesh flat.

Here is my 3D design.  My design may match your needs, too.

My print is made in PETG 1.75mm Aurarum clear filament, with 0.2mm layer height and 15% infill on a PRUSA I3 MK3S printer.

I hope you can find this design useful, too.