50mm lens holder

This is a lens holder for a molded lens that is 50 mm in diameter and has an edge flange. A semicircular slot 3 mm wide holds the edge of the lens. Adjust the SCAD file for the lens and mounting hole dimensions you need . Lens holders are useful for demos and optical experiments. The specific lens shown in the photos is "50mm Optical Glass Lens Collimator Plano-Convex for Led Projector" from eBay. On my printer, the slot ended up at 2.7 mm wide, about 0.3 mm too narrow for the 3.0 mm lens edge, so I had to scrape it out a bit with a knife point. Unless your printer is more accurate than mine, you might want to enlarge the slot a bit in the SCAD.

You can print two of them and stack one upside down on top, to fully capture the lens.

For a different 50mm lens holder that fits on a yardstick, see http://www.thingiverse.com/thing:49942

For a similar holder for a 75mm lens, see
http://www.thingiverse.com/thing:1917482

The blue item is what I printed from the enclosed file. The black one is a similar shape I made by hand from Kato polymer clay, which turns from clay-like to a hard plastic (PVC) after baking 10 minutes at 150 C. That was my very first try at a clay model- crude, but functional.

I tried printing this in ABS two different times on a Makerbot dual with 110C heated bed. The first time it worked fine, and that's the one you see in the photo. However I printed without a raft and it cracked off the bed just at the moment that the printer finished, so I got lucky. The second time it popped free at about 1/5 done, so maybe I need a raft or some different settings.

The hand-carved polyclay version is a lot less clean looking, and more work to make, but it also does the job and didn't require a printer at all! Although having the actual 3D item in hand was very helpful in carving out the rough copy.