I used to think propane forges were just for beginners. Boy was I wrong.

Honestly, I spent years running a coal forge and talked down on propane setups. Last month I visited a buddy's shop in Springfield and he fired up his homemade propane forge to show me how he heat treats stainless. The temperature control was spot on to the degree, no guessing at colors. I still love coal for the feel but I'm actually building a propane forge now for precision work. Anyone here run both and have a favorite for different jobs?

3 comments

3 Comments

averymartin28d ago

Whoa, hold on @mary_martin22, you're telling me you've never seen a propane forge hold steady for a heat treat? That's wild. I get that coal feels like the soul of the craft, but have you actually tried running a stainless soak in a propane forge with a PID controller? It's not just "clean," it's dead simple. Your buddy must have had a good eye or a thermocouple, but my question is - how long did it take him to dial in that coal forge for a 1950F soak without burning the edge off the blade? I bet @stella_lane could tell us the real difference in setup time between the two, because I've seen guys spend an hour choking a coal fire just to hit a specific temp for stainless, and then they still have to babysit it the whole time.

stella_lane29d ago

Oh for sure, @mary_martin22 you're hitting on the exact reason I was so shocked too. My buddy's got a digital controller on his propane forge, something from an old oven kit, and it holds temps within like five degrees for hours. That precision is just not happening with coal unless you're staring at the steel the whole time. I still think coal has this soulful quality for forging blades and doing heavy work, but when you need the steel to hit exactly 1950F and soak there for a specific time, propane is just way easier. Plus there's no ash or clinker messing with the atmosphere in the forge, which matters a ton for stainless. I'm keeping my coal forge for weekends and big projects, but the propane setup is going to be my go-to for anything with a tight heat treat window.

mary_martin2229d ago

Wait, you went from coal to propane for stainless heat treating? That is honestly shocking to me. Coal is like the wild west of heat control, and propane sounds way too clean for that kind of precision work, but I guess I'm wrong. Did your buddy set the temp with a digital controller or did he just have a really good eye for the color? I always figured the stainless crowd would stick to electric kilns, not propane. I mean, you can get propane to hold steady, but that just seems like overkill when coal does the job for shaping.