While phone cameras are getting really amazing I still like my old Sony because it allows me to fiddle with exposure etc.; It has a very good sensor and lens.

I recently dented the lens casing on a rock. The dent prevents the lens cover from closing and leaves the lens unprotected in my bag.

I found a few candidates for lens caps on the Internet but the reviews had conflicting information on whether they’d actually fit. So I decided to print my own.

I followed this tutorial for Blender. After about 1h of modelling I arrived at the following model:

When you click on the model image to zoom in you’ll see that the diameter is 6.175 cm. This is 0.175 cm of rim, and exactly 6 cm for the cap diameter. In retrospect I should have reduced the diameter by about ~0.05 cm. While the cap fits on perfectly there is no resistance when removing it, and it can easily fall off by itself. I fixed that by adding extra material with a coating of super-glue on the inside.

After a nerve-wracking 2 week wait (will it fit??) and a total of $18 including shipping my lens cap arrived. It’s more red in real life than it looks on my terrible phone camera:

I’m quite happy with it!