used. In the block-plane, the bevel is on the upper side.”
“But what are the double irons for in the other planes?” asked Thad. “I have seen them, but I never knew what the extra one was for.”
“That is a sensible question, Thad. If the grain of the wood were always straight,—that is, parallel with the length of the board,—a single iron would answer very well. But wood, like some men and women, is sometimes cross-grained; The tendency of the iron in the plane is to follow the grain as far as the face of the plane will permit. The edge of the upper iron is curved a little, so that it prevents the cutter from going in too deep; and it turns the shaving up in such a manner that it don’t choke up the opening. The upper iron also stiffens the lower one, which is now made very thin compared with the custom made years ago.
“I judge that some of you have used a plane, or tried to do so. If so, you have found great difficulty in getting your tool set right. These planes are of the latest pattern. In old planes the iron is set with a wooden wedge. You have to drive in the wedge with a hammer; and, when
you take it out, you have to strike several smart blows on the top or the back end. To get the iron just right bothers the beginner more than any thing else.
“In these planes there are no wedges. A little lever is moved, and the iron is fast; as you may see by trying it. Under the iron you notice a screw, which may be turned by the thumb without taking the hand from the plane. By turning this screw to the left, you force the iron down so that it cuts a thicker shaving. Turn it to the right, and you get a thinner shaving. You have no use for a hammer, unless it be to knock the iron to one side or the other; for the edge of the cutter must be exactly parallel to the surface of the plane. That will do for planes.—What next, Dory?”
A patent bitstock, very beautifully made, with the metal parts nickel-plated, was handed to the carpenter. The boys knew what it was, though most of them had never seen one of that kind.
“This is sometimes called a brace, though bitstock is the more common name in this country. It has some peculiarities,—the first, that the socket will hold a bit of any common shape, the
holder adapting itself to the form as it is screwed up.
“The second is a ratchet-arrangement, by which a hole may be bored close to a partition. With an ordinary bitstock, you cannot bore a hole within three inches of a wall, or any other fixed body. After adjusting the ratchet, you may turn the crank half around, or as far as you can; then you can carry the crank back without turning the bit, and repeat the movement as long as may be necessary.”