Here’s part of a recent email letter I received and my reply. It brings up a particularly important point for those considering using charcoal… as I recommend (see COAL VERSUS CHARCOAL below).
I read with interest your position on charcoal, my concern is if charcoal gets as hot as coal. The only coal I have used in my primitive forge has been coal I picked up along a railroad track… Bottom Line, CAN I HEAT AS HOT WITH CHARCOAL? Where can it be obtained locally? Indeed, my coal was pretty smoky stuff, but it did get hot, but, I still could not forge weld with it. John Logan Branson, Missouri
Yes, you can most definitely reach welding heat with charcoal and thats about 400-500 degrees hotter than you need for normal forging activities. Keep in mind that there are many areas of the world where coal was (and still is) relatively scarce or nonexistent. Since the beginnings of metallurgy in those areas the forges have been fired with charcoal with great success. I get my charcoal in Yellville, Ark from the Ozark Oak charcoal company You can buy a few bags at local grocery stores and give it a try before committing yourself to a trip to Arkansas for a big load.
Whatever you do, dont try forging with charcoal briquettes they contain coal dust, green sawdust, and sand as well as actual powdered charcoal. The heat they produce is lower than youll need for good forge work, their burn rate is poor for forging (thats why the green sawdust has been added to slow the burn rate and make them last longer on the cooking fire), and they leave a really nasty residue (mostly sand) in your forge bed. While there IS carbon monoxide produced when burning ANY charcoal, most forges or forging locations are drafty enough to make this a non-issue. Just be sure you have good ventilation and youll have no problems with that particular by-product of the burning activity.