The choking of a plane is the stoppage of the throat by shavings. It may be due simply to the fact that the cutter is dull or that it projects too far below the sole of the plane. In a wooden plane choking is sometimes due to the crowding of shavings under some part of the wedge. When the adjustable frog in a modern plane is improperly placed choking may result. The frog should be far enough forward so that the cutter rests squarely upon it.
Choking may, and most commonly does, take place because the cap does not fit down tight on the cutter. This happens if the cap be nicked or uneven. In consequence, minute shavings are driven between these two irons and choking soon results. The remedy is to sharpen the cap, so that its edge makes a close fit with the cutter. The fit may be made still tighter by rubbing with a screwdriver the edge of the cap down on the cutter after it is screwed in place.
In no tool is it more important to keep the cutter sharp than in the plane. To remove the cutter, in order to sharpen it, first loosen the clamp lever and remove the clamp. Carefully remove the cap and cutter taking pains not to let the edge hit any part of the plane, then using the clamp as a screwdriver, loosen the cap-screw and slide the cap back along the slot in the cutter, where it can be held fast by a turn of the cap-screw. The edge is now free and can readily be whetted. When the cap needs to be entirely removed, for instance, for grinding, after it has been slid along the cutter slot, as before, it is turned at right angles to the cutter, and then slid down the slot until the cap-screw unbuttons from the cutter. The object in sliding the cap up the slot before turning it, is to prevent the danger of injuring the edge. Some caps are now made with the buttonhole at the upper end of the slot.
After sharpening, (see under sharpening, [p. 117].) the order is reversed for replacing the cutter. The cap is set at right angles to the cutter, the cap-screw dropped into the slot, the cap is slid up the slot, and turned into line with the cutter, and then slid down the slot till the edge of the cap comes quite near the edge of the cutter. Then the two are held firmly together with the left hand until the cap screw is turned tight.
In replacing the cutter and cap in the plane, care should be taken not to injure the edge and to see that the Y adjustment lever fits into the little slot in the cap; then finally the lever is thrown down tight. Then, by turning the plane sole upward and glancing down it, the proper adjustments with the brass set-screw and lateral adjustment lever are made. When the plane is not being used, it should rest either on a pillow (a little strip of wood in the bench trough), or on its side. In no case should it be dropped sole down flat on the bench.
The block-plane, Fig. 108, gets its name from the fact that it was first made for planing off the ends of clap-boards, a process called "blocking in".
Fig. 108. Section of Block-Plane.
The names of the parts of the Bailey block-plane are6:
1. Cutter or bit or plane-iron.