possibly dummest question of all: using a fireplace

[overmodulated]

Folks: I see the orange coals burning brightly at the base of my woodburning fireplace, which gets plenty of air from the chimney draw, and have to wonder: is there any solid reason I couldn't heat treat a knife in there?

Is it just not enough heat compared to a coal forge with hand-cranked air supply or a gas forge?

Thanks

[David Einhorn]

No question is dumb. Please remember to add your location in the User CP at the top of the page so people can tailor answers for resources to where you live.

Unfortunately, your wood-burning fireplace is not hot enough to heat treat a knife. Paper burns at Fahrenheit 454 (thus the name for the book we were forced to read in school), so your wood fire is not likely to be much hotter than that.

[pkrankow]

The grate in my fireplace turns cherry red at times, and the previous grate sagged under its own weight it was so hot! The ignition temperature is low, but a sustained flame is much hotter, and the ember bed is chemically no different from a solid fuel forge burning charcoal.

Some fireplaces require the door to be shut to operate properly, and some look pretty, but are not able to have hot fires. The time it takes to coke enough wood to have a good ember bed may make this impractical,

I would not want to forge around carpet, upholstery, or wood flooring either.

Phil

[MattBower]

I've gotten steel orange hot in an open wood fire, and I've gotten soda lime glass hot enough to get quite soft -- somewhere north of 1400 F, maybe a couple hundred degrees north of there. So yeah, you might be able to heat treat simple carbon steels in your fireplace. I wouldn't try to forge that way, though.