Design Features

• Ten different mounts: ambient, printer (v-slot), and filament storage (reel & dry-box)
• Push-and-twist the sensors into the mounts
• Ports are well ventilated
• Good plate adhesion with minimal supports
• Tested and resolved designs

BONUS link to a battery cover that stays on securely: https://www.thingiverse.com/thing:6682187

What You'll Need

• Search for "round humidity sensor" and these will pop up; outside diameter is about 45mm. They're cheap and prolific (like my ex).
• You'll need fasteners for some of the mounts: one screw for the wall mount, two M4 screws for one version of the filament dry box mount, and two M3 threaded inserts plus two M3 screws for the other. The V-slot mounts need M4x10 screws and t-nuts.

Versions

• BOX MOUNT M3 INSERT: reverse mount for inside a dry box with 60mm spaced holes for heat-staked M3 thread inserts.
• BOX MOUNT M4 TAP: as above but with tap-drill sized holes for two M4 screws.
• DESK STAND: for flat surfaces to give you a baseline ambient reading.
• REEL HUB MOUNT: snaps into cardboard Polyterra® (https://polymaker.com/polyterra-pla-info/) and Overture® (https://overture3d.com/) reels to monitor humidity inside bags. Please DM me if they fit other reels.
• SHELF SLOT MOUNT: clips into key-holes of shelving unit, like the ones used here: https://www.thingiverse.com/thing:5246240
• V-SLOT FRONT MOUNT: screws into 2020 V-slot with visible fastener for ambient or printer enclosure reading.
• V-SLOT REAR MOUNT: screws into V-slot from the back.
• V-SLOT TOP MOUNT: screws into extrusion with hidden fastener: attach to printer before inserting sensor.
• V-SLOT XTENDED REAR MOUNT: screws into V-slot from the back and has an extensions which clears extruder carriage on Ender 3 v2 (and others, hopefully... let me know). Use with this PiCam mount to view it remotely: https://www.thingiverse.com/thing:5301045
• WALL MOUNT: use screw with max shaft diameter 4mm, head diameter 8mm and head height 4mm.

Assembly and Use

• The hygrometers are retained in the mounts with a bayonet fit: the ambient mounts read correctly when installed (horizontal display), but the other ones allow you to rotate them so they can be mounted sideways or upside down (there are small marks on the back to help line the display up nicely).
• The point of the exercise is to be on top of your humidity mitigation strategies: from resealable bags and home-made dry boxes to inside your printer enclosure. There are some great YouTube videos on this topic.
  
  
  Kill the snap, crackle and pop!

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Found these after the fact (always hated homework):
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