Coal Forge Fires :

Management and Cleanliness

Carbón, charbon à bois, Holzkohle, Kohle, kol / stenkol, houtskool, koolstof

Coal Fire management

Fire management can only be described in very general terms because of the variables which include infinite grades of coal and nearly infinite variations in forge design and construction. The general process follows.

The above assumes a good coking grade of bituminous coal and a fairly normal bottom blown forge with fire pot.

Coal Reserve:

This is the area of the forge where extra coal is kept. Technicaly the center of the forge and firepot is only about a foot square or less. This is all that is needed for a very small forge like a brake drum forge. However, during the day a smith may burn as much as a bushel of coal. Full size forges are usualy about 30" by 40" (750 x 100mm) with the firepot centered toward one end. All this excess area is primarily for fuel storage so that the fire can be convieniently fed as needed.

Some may argue that the larger area is to support larger work. This is true but it is a secondary purpose or benifit of the first. With large and small forges alike we often need stock supports for long or unweildly work. Wheelwrights often had supports on the front of the chimney to hang tires so they did not settle too deep into the fire.

Wet Coal, Dry Coal, Dirty Coal:

Depending on the type dry coal starts easier. Some coal absorbs moisture and is thus harder to start. But in general coal is coal and what moisture it has was bound into it in the ground eons ago. However, I like having some dry coal to start a fire.

Dirty coal is a different thing. Dirty coal is hard to get started, hard to keep burning, causes more scale on metal and is nearly impossible to weld with.

If coal has been dumped out of a forge where much of it was burnt then you have, coal, coke, clinker and ash. When smiths dump their forges they generally pick out the larger lumps of coke to use for welding fires, the obviously clean coal that can be easily shoveled and scrap the rest that is mixed with ash and clinkers.

Coal that has been shoveled off the ground or the bottom of the pile at a coal dealers graveled lot is often full of dirt that is just as bad as the ash above. Gravel often gets coated with enough coal that you cannot tell the difference without a sharp eye for shape and texture. Sandy soil causes excessive clinkers, clays deaden the fire and gravels do not burn making cold spots in the fire.

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Copyright © 2002-2005 Jock Dempsey,

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