Introduction: Bifocal Reading Glasses

As I got older I needed reading glasses, which I buy from the local "dollar store" for $2. Currently I need 1 diopter for computer monitors, 2 diopter for reading, and 4 for fine work.

At some point I needed to read a computer monitor and small-font PDA at the same time, so I made a pair of bifocals for $4

This is almost trivial:
1. Buy 2 pairs of identical frameless glasses in 2 different strengths
2. Cut both pairs across horizontally with a hacksaw
3. Sand the cut edges of the lenses so that they are flat and match up  (they won't match exactly because the stronger lens is
  thicker)
4. Glue the bottom half lenses from one pair to the other pair using epoxy resin.