Rear lens caps · STL / 3MF

Fujifilm X rear lens cap to 3D print

A twist-on rear cap for Fujifilm X lenses that you print yourself. It locks like a camera bayonet, prints face down without supports, and can carry your focal length on the face, so you find the right lens in the case at a glance.

Make yours · €2.90Launch price, later €3.90
Fujifilm X rear lens cap, 3D printed, seen from the lens side with its bayonet claws

Locks like a bayonet

Three claws sit in the lens gaps, so the cap goes on in one position. Then turn clockwise (looking at the face) about 40° until the lugs run onto the stops.

Ramp and lock land

Each claw ramps down along the turn, then a nearly flat lock land holds the lug just before the stop. Resistance rises as you turn, and at the end the lug rests on a surface instead of an edge, so the cap sits firmly and wears less. Set just past the measured lug face like on our print-tested mounts; the fit ring in your files confirms it on your lens.

Made for FDM printing

Face down on the plate, no supports. Vertical teeth or flutes hide layer lines, a 45° foot chamfer hides elephant's foot, and the face gets the finish of your build plate.

Focal length, logo or mount code on the face

Optional: the focal length (zooms such as 24-70 too), your own logo or the mount code in big letters, as a flush inlay in a second colour or engraved 0.5 mm into the face if you print with one filament (tip: one wall on the first layer keeps it crisp). The mount code can also sit small above the focal length or logo. With a logo you print the same cap for every lens in your set. Inside, the mount code and the Focus Rings logo are engraved in the floor.

Fits

  • Fujinon XF and XC lenses
  • Third-party X-mount lenses from Sigma, Tamron, Viltrox, Laowa, Samyang, TTArtisan and others
  • Lenses with a longer rear: choose Deep in the generator
Specifications
MountFujifilm X
Outside diameterØ52.0 mm
Height13.7 mm · Deep 18.7 mm
Room for the rear element11 mm below the rim; Deep: 16 mm
GripModule 0.8 gear (63 teeth) or flutes
Print orientationFace down, no supports
Print time (slicer estimate)about 25 min, about 9 g PLA
Fit test ringIncluded with paid files, about 12 min
Files3MF (body + face inlay as one object), aligned STLs, printing guide

Print times are Bambu Studio estimates for an X1C with a 0.4 mm nozzle and 0.20 mm layers. Not every lens has been tested: check the fit before you print the whole cap.

Print and fit

  1. Print the fit test ring that comes with your files: the bayonet zone only, done in minutes.
  2. Put the lens lugs into the gaps and turn clockwise (looking at the face) until it stops. It should turn smoothly and sit firmly.
  3. Print the cap face down on the build plate, no supports. Two-colour faces: keep body and inlay as one object and give each part a filament.

Questions

Which lenses does the Fujifilm X rear cap fit?

Fujinon XF and XC lenses; Third-party X-mount lenses from Sigma, Tamron, Viltrox, Laowa, Samyang, TTArtisan and others; Lenses with a longer rear: choose Deep in the generator. Room for the rear element: 11 mm below the rim; Deep: 16 mm.

Has this Fujifilm X rear cap been tested on a lens?

Not yet on a Fujifilm X lens. The bayonet is measured from parts that fit real lenses and cameras, the lock is set just past the measured lug face like on our print-tested mounts, and every file passes a layer-by-layer support check. Check the fit first: your files include a fit test ring, the bayonet zone only, done in minutes. Print it and try it on your lens before you print the cap. Too tight or too loose? Tell us: the claws are adjustable.

Does it need supports?

No. The cap prints face down on the build plate. Every overhang is at most 50°, and the claws have sloped undersides that build up layer by layer.

Which filament should I use?

Rings without clamps and lens caps: PLA or PETG, 0.4 mm nozzle, 0.20 mm layers, your usual walls. PETG is a little tougher if the cap lives in a bag.

Why gear teeth on a rear cap?

They are the same module 0.8 teeth as our focus rings, so the cap matches your follow focus gear and grips well with gloves. The vertical teeth also hide layer lines. Prefer something smoother? Pick the flutes grip.

What does it cost?

One price per file, focal length and AirTag pocket included if you want them. Your files include the fit test ring to print first.

Other rear caps

All rear lens caps → · Focus gears by lens →