Finally got the right forge weld after 4 tries

I had to decide between a gas forge and my old coal one for welding a bar of 1080 and 15n20. I stuck with the coal forge cause I know its heat zones better. Took a few tries but I got a clean billet on the fourth go with no cold shuts. Anyone else still prefer coal over gas for pattern welding?

3 comments

3 Comments

blairm774d ago

Coal's heat control is all about paying attention to the fire color and the wind, not just cranking a knob. One trick I learned the hard way is to burry the billet a little deeper in the coal than you'd think, letting the coking coal do the work around it. The real killer is pulling it out too early, waiting until it's a full, even orange glow across the whole bar has saved me a ton of cold shuts. Fresh coal on top of the fire will steal your heat quick, so I always keep a separate low fire next to it for billets that need to soak a bit longer. Gas is definitely easier to set and forget, but coal gives you that direct feel for the steel's temperature in your hands.

kevinallen4d ago

Have you ever tried building a small trench in the coal bed to channel the air blast? That was a game changer for me. I dig a shallow groove from the tuyere to where I set the billet, and it stops the fire from getting those random hot and cold spots you mentioned. Also, I keep my fire pot pretty shallow, only about 4 inches deep, so I can actually see the heat zones and adjust the coal pile shape as I go.

wadejenkins4d ago

I mean, you mention preferring coal "cause I know its heat zones better" but honestly, I've gone the other way on this. I've been using gas for the last few years for pattern welding and I just get way more consistent results. Coal is great for a lot of things but I always had trouble with hot and cold spots in the fire, which caused more failed welds for me personally. Once I got a good gas forge with a kiln shelf and some kaowool, the even heat made it way easier to get clean billets on the first or second try. Not saying you're wrong or anything, just that for me gas took the guesswork out of it.