Got an autocollimator with no lens caps? Not any more! I wanted to protect the optics on my new to me Hilger and Watts TA130-1 so I made these! Took a few attempts to get the fit right so I'm uploading them here just in case anyone needs them! (Print in vase mode! They're solid cylinders otherwise!) What's an Autocollimator? It's a telescope for measuring angles! They're really precise and versatile, as long as the lenses aren't messed up from being kept without a lens cap! How did I design this? I measured the parts the caps should fit on as 38.14mm for the front lens tube (1 1/2in) and 30.60mm for the eyepiece (a hair over 1 3/16in??) and for my ender 3 with stock nozzle, standard quality using Filamentum crystal clear pla I found an outer diameter of (lens tube or eyepiece) + 0.9mm gave a fairly solid press fit. If your autocollimator has different sized bits, this could be a good starting point (perhaps even for a theodolite, a dumpy level, heck even a generic telescope for looking at stars! If your diameters change much you might need to scale the tolerance a bit). What's vase mode? This is a setting in your slicer which only prints the bottom of the model plus a single pass of the outer wall. In Cura it's called "spiralise outer contour" and it's in the special modes section!