Just wanted to share a retrobright technique I have been messing around with and having success with. Sunlight is not always a guarantee where I live, and even on sunny days you get about 8 hours of good sun to work with. Forget about it in the winter. I have heard not many success stories with UV LEDs or CFLs as a substitute.

I had noticed that days when we didn't get much sun but I used hot water had much more progress than days where I did not use hot water. So that got me thinking that heat might be able to be used as a substitute for UV light.

I cut a small piece...