SO, ABOUT THAT PROBLEM,

I've come down to three ideas

1. After heating the steel, I will time how long it takes return to normal temperature.

2. Liquid temperature strips - you stick them onto the object you want to measure.

3. Place steel in water, take temperature of water, then time how long the water takes to cool back down.

So, there you have it. Let's just hope we see a bit more sun now!