FlapCap - Never-Lost Camera Lens Cap

I like the idea of always being ready to capture a moment on the go, but traditional lens caps have always been somewhat frustrating for me. I’ve lost countless caps over the years, and I’ve never liked having to either put them in my pocket, where they can collect dust that ends up on the lens, or attach them with strings that leave the cap rattling against the camera or getting caught on things.

So I designed FlapCap to solve those problems.

FlapCap is an always-attached lens cap designed for photography and filming on the go. It keeps your lens protected and clean while still giving you fast access when you need to take a shot, without having to remove the cap completely or worry about losing it.

Features

- Always attached

- Mounts using the filter threads found on most camera lenses.

- Bistable hinge

- Stays securely either open or closed, so the cap does not flap around or rattle.

- Quick open and close

- The hinge snaps with relative ease between positions for fast, simple operation.

- Two versions included :

- Slim version for the cleanest and most compact setup.

- Magnetic version with a wider frame designed to hold magnets for additional closing security.

Compatibility

I used my Samyang/Rokinon lens as the reference for this design, so the currently uploaded models are made for 49 mm filter threads .

I may add additional thread sizes in the future.

Printing

The hinges need to flex a little, so I recommend avoid anything too brittle. I’ve successfully printed FlapCap in both PLA+ and PETG using a 0.16 mm layer height . No supports are needed.

The printed threads can be a little finicky at first. Because both the lens/filter threads and the printed threads have fairly fine tolerances, take your time when attaching the cap for the first time.

Hinge

Snap the top and base together, then insert a piece of 1.75 mm filament through the hinge holes.

There are two ways to secure the filament:

- Leave about 5 mm protruding on each side of the hinge and carefully melt the ends to form small retaining heads.

- Print the included hingecap STL and glue one cap onto each side of the hinge to trap the filament in place.

Thank you for trying out FlapCap!