More light fixture related stuff

There was some streetlight fixtures included in the lightning fixture bundle I recently acquired. Some of these were cracked and needed some repairs.

The repair was done using Araldite epoxy. 

The gluing procedure:

1. Warm up the sauna to 90 degrees Celsius.
2. Clean up: Basic clean-up of the lenses with soap and water.
3. Sanding: sanding of the crack edges with 400-grit sandpaper.
4. Clean-up: This time with isopropyl alcohol.
5. Application of glue: Pried the cracks open and applied epoxy liberally.
6. Curing/tempering: Carefully placed the lenses in sauna to cure and temper the glue.

Tempering of epoxies is something I learned from 3M datasheets as they claim that tempering the epoxy might increase the yield strength of the glue by 10-20%.

Epoxy might get yellow over time as it isn't uv protected.

The dates on these say that they were made in 1988. So maybe a little yellow epoxy doesn't matter.