Easy Filament Drybox - snap in place, no bolts

Scanned to fit - Filament spool holder and roller system for an inexpensive cereal drybox. Spool is custom designed to accommodate several spool sizes from 250g to 1kg.

This set up is made to fit perfectly into Vtopmart Food Storage Container Set, available on Amazon for $22.95 for a set of two. No bolts, screws, or nuts required. Just print the parts and slide together, then slip the whole assembly into the cereal box for a perfect fit! You can see in the photos that the box can be turned upside down and the roller assembly holds in place via friction.

I designed this setup using an Einstar handheld scanner to capture a 3D image of the cereal box’s exterior, then reduced it on the X-Y axis by the 3mm thickness of the plastic. The resulting exported stl was then used to slice the roller assembly in Blender to the perfect size. The result, again, is a perfect fit with very little hardware required. The only hardware needed for the roller assembly are (4) 8x22x7mm sealed bearings per box, available on Amazon in an eight-pack for $6.95, and one M6 Pneumatic Straight Fitting for the filament guide. I created on Blender a donut-shaped guide design for super smooth sailing on the filament feed. (The guide has a pre-threaded hole that’s tapered wider at the front for ease of threading the PC4 connector. see the filament guide at https://www.thingiverse.com/thing:6416246)

I added a silica gel cannister to each box to complete the finished product – Amazon Wisesorb 40 gram.

The rear spool is lowered by 2mm from the front spool to allow more room at the front of the drybox, and to balance the load once the filament starts pulling (weight distribution shifts ever so slightly with even height spools).

Overall, this project came out great!! It’s super easy to load and unload, and even easier to put together.

Minimal parts needed:

(2) Vtop Food Storage Container Set – pack of two for $22.95 – Amazon: https://www.amazon.com/gp/product/B095HSKJS3/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1

(8) 8x22x7 miniature ball bearings – Amazon pack of 8: https://www.amazon.com/gp/product/B00NX23HGQ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

(2) PC4-M6 pneumatic connectors for Bowden tubes – Amazon pack of 10 for $6.99: https://www.amazon.com/gp/product/B01NANKRTD/ref=ppx_yo_dt_b_asin_title_o09_s02?ie=UTF8&psc=1

(2) desiccant packs of your choice. I used Wisesorb canisters – Amazon pack of 4 for $13.97: https://www.amazon.com/gp/product/B0B56CNXKZ/ref=ppx_yo_dt_b_asin_title_o08_s00?ie=UTF8&psc=1

Instructions for each drybox: (see added photos)

Print the Left and Right conforming bases on their sides with bearing holders facing up. Supports are necessary because of the custom cut shape.

Print two of the crossbeams lying flat, two of the 76mm multi-roll spools standing upright, and one filament guide – no supports needed for any of these pieces.

Mount one of the bearings on each of the roller supports on one side of the finished base frame.

Add the spools and place another bearing in the end of each.

Slip one of the crossbeams into each of the rectangular holes in the front and rear supports.

Place the other half of the frame on top of the assembly and press fit the pieces together.

Put the entire roller assembly into the cereal box. It should fit perfectly, and the rough outer edges of the print will hold it firmly no matter which way you turn it.

Drill a ¼ inch hole in the center line of the wide end of the box – right across from the 5 Liter mark for the filament guide. (hole can also be drilled lower to match your printer's intake, and filament roll can be flipped to match)

Insert the PC4-M6 connector through the outside of the hole and screw it into the donut shaped guide. The hole in the guide is pre-threaded with a tapered opening at the front for ease of threading.

That’s it! Just snap the lid on and off as needed, and enjoy this super easy assembly!

I printed mine using a QIDI X-Max3. (This printer inspire the drybox design, since the factory spool is mounted on the rear)

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This design was inspired in part by Shinondon's 4L drybox https://www.thingiverse.com/thing:4675588.
The rollers were inspired by Chrlee https://www.thingiverse.com/thing:2221639