This is a simple shelf/tray to hold a common cereal box as would be used as a 1kg filament spool dry box / dispenser. It is designed to enable mounting on top of a standard rail with (3) three 4mm bolts and rail nuts. Securing lugs are robust, but designed to minimize rail occupancy and allow for other mounts and devices to be used in the same space.

This model was printed in standard Overture black PLA:

- 6 walls (overkill)

- 25% infill for extra rigidity (overkill),

- no supports needed.

My printer and storage space is a bit cramped. The shelf was designed to allow approximation with simple line of feed to the printer (CR-10S Pro V2), while also allowing mounting of the factory filament mount and a Sonic Pad on the top rail.

I live in Houston, TX- humidity in my home is routinely at or above 70%. Storing PLA was not a major issue- I'd periodically dry out a spool before any major prints. I've recently moved to using PETG (much more humidity sensitive). I noticed a change in printability with dried filament just 4-5 hours into an ongoing print- hissing, sizzling, messy extrusion, etc. I've started conversion of storage to cereal box feeding sleds (pictured), but could not find an adequate mount or shelf to fit my space needs.

This mount was designed to still allow the OEM filament mount, so a quick print with a roll that is not in a dry box is not an issue (see pic uploaded for clearance). Box is stable in place, through in the future I may design a TPU insert with negative model of the box for added security, We'll see how the box and feed responds after a bit of use. The Sonic Mounts are remixes of another design, modified to use bolts to the rail rather than slip fit arms. I may post those in the future, once I've increased their robustness.

Let me know your successes, alternate ideas, or impressions on your use case!

4L Cereal Box (filament box) shelf for 20mm top rail

0.2mm layer, 2 walls, 15% infill