The Sensuous Gadgeteer
(Page 11 of 11)
September/October 1973
By the Mother Earth News editors
Simple hardness in a metal is obtained through the small size of the metal crystals. This is got by heating the metal to disturb the crystal structure and then quenching it in water. Quenching cools the metal quickly and does not allow the crystals time to grow large before they are too cold to grow at all. Metals thus tempered are hard but seldom supple. If a metal is heated red hot or nearly red hot and allowed to cool slowly, the metal crystals will have time to grow large. The large crystals are soft, and the metal is soft, and that is why a scorch on a chisel means that the chisel has been ruined by too much heat—it shows that the metal is soft. This softening of the metal by heat is called annealing. Annealing can be useful: If you want metal to be soft, anneal it. Annealing glass relaxes stresses in the glass and thus lessens the likelihood of breaking.
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Incidentally if you want to see the crystals in a metal alloy, look at a well-used brass door handle, such as one on a popular public building. You will see a patchwork of rectangles up to 1/8" in dimension crosshatching the surfaces. These are zinc and copper crystals. All metals are composed of crystals. The network surface of a cold solder joint arises when the tin and the lead crystallize out of the melt separately. This separate crystallization of materials out of a melt is put to practical use in zone refining.
Tap your chisels with a wood or leather mallet, not with a metal hammer.
PLANE
The plane is a chisel that peeks through a slot in a flat guide. The plane usually has two uses-cutting large splinters off from the surface of wood planks and removing small amounts of wood from the edges of boards such as doors. When your door sticks in one corner, take down the high place with a plane. The flat guide of the plane ensures that the chisel will take only a controlled bite out of the surface to be cut. If the plane takes too deep a bite into the wood it will catch and rip up chunks of wood. But if the plane takes only a shallow bite out of the wood, and if it is moved smoothly and firmly across the wood, the plane will bring the wood up in uniform ribbons up to three feet long. The plane operates with the grain or across it at an angle, never against it.
The bite, or depth of cut, taken by the plane is adjusted by the knurled nut next to the handle. The tilt of the knife is adjusted by the lever in the knife holder.
Never set a plane down on its face as this will chip the blade.
Set the plane down on its side. Sharpen the blade on the grinding wheel like any other chisel.
Guitar and violin makers use large precision planes for finishing the surfaces of the thin wood boards from which they construct their instruments.
The folks at Running Press in Philadelphia tell us that The Sensuous Gadgeteer will be out this fall ... in fact, it might very well be available by the time this issue reaches you. The book will sell for $3.95, a modest price for over a hundred great-big, information-packed, paperback pages. After all, if Abler can convince you that you really don't have more than the usual number of thumbs, the boost to your ego alone will be worth the four bucks ... and when you throw in all you'll be able to do for your homestead with Bill's help, TSG just about has to be one of the best bargains you'll find anywhere.
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