Quick-Off Binocular Cap

Perfect for shelf-stored or grab-and-go binoculars.

We keep a pair of binoculars sitting upright on a shelf by our back door, ready to grab if anything interesting shows up in the yard. Unfortunately, critters are fast, and fumbling with tight-fitting eyepiece caps is a great way to miss the moment.

This is a simple, one-piece binocular eyepiece cap designed to fit loosely so it can be removed instantly with one motion. It covers both eyepieces and is long enough to work whether the binoculars are set to their narrowest or widest configuration — across the full interpupillary distance (IPD) adjustment range.

The goal here is quick protection from dust when stored, without slowing you down when it’s time to look.
 

Dimensions
The internal dimensions of the cap are listed below. It can easily be scaled in your slicer to suit different binocular sizes.

• 120 mm long
• 47 mm wide
• 21 mm tall
   

Notes

• Loose fit is intentional for fast removal
• FreeCAD design file included for easy modification
• The filament used in the photos is Bambu Lab Galaxy Nebulae (the color in the photo showing interpupillary distance is ridiculously exaggerated)

Links

FreeCAD - 100% free and open source 
[https://www.freecad.org/](https://www.freecad.org/)