Popular Woodworking 2005-10 № 150, страница 77

BLACKSMITHING AT A GLANCE

Blacksmithing is a hasty sport. Unlike woodworking, where you can step back and contemplate a cabinet's lines or run your hands over a planed surface to check its smoothness, working with hot iron means moving fast. You've only seconds before the malleable, bright orange steel has faded nearly to black, and any further hammering is likely to impart stress fractures. Back into the fire it must go.

You can easily make handsome, functional tools from scrap. I've made froes, Welsh spoon carving knives, a bruz (for cutting beads on the lathe), travishers, spoke-shaves, turning chisels and gouges, drawknives and other tools. Today I'm making a couple holdfasts for a traditional woodworking bench.

At forging temperature, from about 920° F to 2,200° F (distinguished by a bright orange to yellow color), steel has great plasticity. It can be cut, flattened, thickened, bent and tapered (see the photos below for a brief overview of the making of a holdfast).

To the uninitiated, probably the most mysterious aspect of the smiths' art is the discerning of steel's temperature by its color. There is

no exact method of knowing the heat of the steel in the fire, and for the actual forging it's not that critical. When the orange has faded, and the steel begins to resist the blows of the hammer, it's time to put it back in the fire. A blacksmith quickly develops an eye and a feel for his material.

Perhaps the only exactitude comes about when heat treating, which is actually a three-step process. As a result of all the heating and hammering, steel becomes hard and brittle and may develop internal stresses. So the first step is to anneal it. This is done by bringing the steel up to a good forging temperature, then plunging it into a container of vermiculite, lime or wood ash so it can cool slowly, relieving any internal stresses. Any grinding to shape should be done now (once the steel has cooled) while the steel is relatively soft.

The next step is hardening. I do this by bringing the steel to just above its critical

Steel can be cut easily when it's hot. To trim the shaft of this holdfast I first heat the section that will be cut (above). I then pound this section over the edge of a cut-off hardy installed in my anvil.

Here I'm heating the steel. A charcoal forge (this one's an old riveter's forge) is the simplest, cheapest way of bringing steel up to forging temperature. I keep the fire as concentrated as possible for the work I'm doing and feed charcoal into the fire as necessary to keep it going.

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Popular Woodworking October 2005