I use this case for holding eyepiece lenses. The inner diameter is about 48mm and collapses to about 88mm. The two parts are threaded together and can be assembled in the dark easily because of multiple parallel threads. They turn only a third of rotation if collapsed all the way.

I printed these parts in white PETG.

No

.3

The inner piece was printed with a 4 wall setting the outer part with 1 wall. Using infill does not work with my equipment on these parts.