This is an almost got it project. I damaged some clip on magnifiers I use and figured I should probably make a spare pair. As I bought some Poundland magnifier glasses a while back for the pads, I threw the frame but hung onto the lenses. I figured I would have a go at making some half frame clip ons. First job work out how to cut the lens in two, or rather how to grip it without marking or damaging it.

This setup seemed to work, IKEA coffee stirrer stick snapped in half using the universal vice with handle removed clamped on the mill. The cutting blade is carbide tipped from Aldi for one of their small saws. They are great for cutting Perspex.

It took quite a while doing the cutting as the setup isn't that rigid so gentle cuts, it also left a crystal clear finish on the cut parts.

A bit of gentle de burr left the lenses ready for the intended frame. Since I managed to print some arm covers I thought I would push my luck trying to print a frame.

The hardest part was trying to draw the lens outline and bevel that traps in the frame. I didn't do too good a job on the bevel as its tiny and really too small to print at 0.1mm layers as well as being curved in 3 dimensions. Still, I gave it a go and could see the slicer had struggled to make smooth paths as I was working with so little material. A much smaller nozzle might have had better luck.

The finished lower frame is not a success, it was difficult to print and at this scale lots of blobs caused me grief in the slot to pickup the bevel. I could redesign the frame for printing, or just make some form tools to roll a frame out of copper wire that will grip the lens properly and be easy to form the correct shape out of. In this case a failure, but it's still pushing the boundaries.
As Dirt Harry would say "a man's got to know his limitations"