We do quite a bit of knifemaking (crooked knives, mostly) in our longer courses. In trying to keep things as simple as possible, we use the campfire or woodstove to anneal the blades, and an open fire to temper them as well. We’ve got a coal forge with a hand crank blower, but we’re always working to simplify the process, and this is a significant investment.

I’ve been watching a youtube channel called GreenPowerScience where they have a lot of great videos on simple green technology. They do a lot with large fresnel lenses, using them to cook, make steam engines, etc. They use big lenses mounted into wooden frames.

I was thinking about using one for is a solar forge for knifemaking/blacksmithing.

Check out this video:

I don’t know the exact temps needed of any of the specifics, but with a big enough lens it could definitely be done. And in the end it would be much cheaper than a coal or gas forge; no blowers, no fuel, no moving pieces. I think it will be a fun research project for this year.

Has anyone ever thought about/tried this?