Dyna Dry Box - Support-free Round Hygrometer, PTFE Loop For extra filament, and Box Warping Brace

A quick and dirty in-Orca remix of a solid design based on:

• Using cheap cereal holders e.g., MCIRCO Airtight Food Storage Containers (4L /135.2oz), which may have slightly warped walls that rub on cardboard spools.

  • Change = Added a Box Wall Brace

• Being too lazy to recess the bearings.

  • Change = Not sure if recessing was intentional (maybe to maximize roller width?), but the rollers have been shortened a little (model has been split and reassembled to allow further length customization).

  • FWIW, with 0.8mm nozzle printing tolerances were a little off. I heat the ends of the tubes (briefly) (flame or boiling water) to soften the plastic before installing the bearings. The softened PLA helps the bearings seat easily when pushing the tube over the bearing.

• Preferring the round hygrometers that go to 10% RH e.g., Rojuna 10-Pack Mini Thermometer Hygrometer, and not liking to print with supports,

  • Change = Added a hygrometer holder that can print without supports (45° overhangs) and a lock ring option to hold the hygrometer in place when those values have to stay exactly horizontal and you don't want to reopen the box to fix it... :)

• Not wanting unwound filament hanging out in the air.

  • Change = Added a second "outlet" for use as an inlet into which excess filament can be pushed. The outlet PTFE tube is then bent over and pushed into the inlet making the hole thing (pun intended) airtight. Longer PTFE (using 6" here as it fits our printing setup better) is probably better as the looser "U" bend reduces the stress on the filament so less likely to break. Use the cap (or stuff something else into the small inlet hole) when printing from the box.

  • FWIW, Filament can also be pinched in the valleys of the Adapter - it's an option if you want to hold a short length of the filament; consider printing a second cap to keep the air out too.

• Being too cheap to use metal PTFE couplings (and looking for some other benefits).

  • Change = This Adapter design was created for another project and reused here. Fusing these 2 Adapters together also makes tightening the collar rings easier. They should snap through the holes in the Lid Double Pass Through with a gentle push then use the Adapter Nut to pull the Adapter base against the inside of the Lid Double Pass Through.

• Being a bit too cheap, generally

  • Change = Removed some material from the Body. Didn't seem to impact performance as there are minimal lateral load on the body (unless, like us, you knock the whole stack of dry boxes off a table with full filament rolls inside - then you might find a roller fin or two may break...and a couple of boxes may also crack. Oops ;) )

• Being impatient

  • Not really a change but we're using 0.8mm Nozzles to print on a Bambu A1M (Unfortunately the PTFE holders still need 0.4mm @.12mm layer height (mostly for strength...). The print settings in the .3mf should produce a full set of parts with a 0.8mm doing the heavy lifting in ~3 hours (or 1 hour using 3 printers...). Not sure what the benchmark is for 0.4 production....didn't have the patience to figure it out ;)

Some cereal boxes appear to have slightly different opening sizes or use different gaskets. The Inside Ring part of Lid Double Pass Through assembly can be resized (in the .3mf file) quickly (.3mf assembly part = Inside Ring - Outside). Use the scale tool to set the inside diameter of your actual container outlet size  (including the gasket, if present), or simply measure the diameter of the ring on the lid door. Slightly oversizing the Inside Ring - Outside assembly part (e.g. +0.7mm to the container outlet diameter, so 60mm+0.7mm = 60.7mm ) puts pressure on the Container's gasket, making it snug when inserted and airtight when left alone (a check for a snug fit is that the Lid Double Pass Through shouldn't rotate easily). And consider using scarf joints if you're feeling extra fancy and want an even nicer seal... :)

Print settings are attached to some parts/modifiers in the .3mf. But, default PLA settings with 3 top and bottom layers, 2 walls, with slow (20mm/s) small perimeters typically kicks out good working, airtight parts.

FWIW, I'm using 100g of desiccant inside the spool so I can see the color change. This config is kinda redundant as there is a hygrometer in the box, but it's a belt and suspenders setup.

Hope this is useful to someone or two. ;)

Lots of credit to @Dynarun and @dr13st for the their very fine work.

Please excuze typos and silly humor.