The Handyman's Book of Tools, Materials, and Processes Employed in Woodworking. Paul N. Hasluck
joiners’ cramps (non-patent) resemble Fig. 112, a lengthening bar being supplied with them at an increase in price of, roughly, 60 to 80 per cent. There are several makes and many differences in detail, but Fig. 112 illustrates the type. There are a number of patent cramps for sashes and general joinery, of which Crampton’s appliance (Fig. 113) is sufficiently typical. The right-hand jaw can be set at any position on the rack. When the work has been inserted the right-hand jaw is pushed against it tightly, and the lever handle gives instantaneous adjustment. The joiner has a choice between a very great number of cramps. When jointing up thin stuff, if an ordinary cramp is used, there is a great risk of the material buckling up, and the joint being broken. This risk is obviated largely by the use of the cramp shown in plan and side view by Figs. 114 and 115, which are sufficiently explanatory when it is said that the cross pieces slide upon the side pieces. one sliding bar being made immovable by iron pins placed in holes in the side pieces. In cramping very thin stuff, place a weight upon it before finally tightening the hand screw.
Fig. 104.—Braced Sawing Stool.
Fig. 105.—Bolted Sawing Stool.
Fig. 106.—Sawing Horse.
Fig. 107.—Bench Holdfast.
Fig. 108.—Wooden Holdfast Cramp.
Fig. 109.—G-cramp.
Fig. 110.—Hammer’s G-cramp.
Fig. 111.—Sliding G-cramp.
ROPE AND BLOCK CRAMP.
Fig. 116 illustrates the method of cramping up boards with rope and blocks. The wood blocks A, about 4 in. long and 1 1/2 in. square, are placed on the edges of the boards B, and a rope is passed round them twice and knotted. A small piece of wood is then placed between the two strands of rope and twisted round. This twisting draws the rope tighter on the blocks, there-by cramping the boards together. Three of these sets would be sufficient to cramp a number of long boards.
Fig. 112.—Sash Cramp.
Fig. 113.—Crampton’s Patent Cramp.
WEDGE CRAMP.
A more serviceable cramp is illustrated by Fig. 117. A piece of wood A, about 2 ft. 9 in. long, 6 in. wide, by 1 in. thick, is planed up. On each end of this are fixed blocks B, 6 in. long, 1 in. thick, and tapering in width from 4 in. to 2 in. The boards E to be cramped are placed on the appliance, pieces D are laid against the edges of the boards to protect them, and the wedges C are then driven home. These wedges should be about 10 in. long, 1 in. thick, and tapering in width from 4 to 1 1/2 in. The whole of this device should be made of hardwood, except the packing pieces D, which should be deal, so that if too much pressure is applied to the wedges any injury threatening the edges will be taken by the packing pieces rather than by the boards.
Figs. 114 and 115.—Cramp for Thin Work.
Fig. 116.—Rope and Block Cramp.
Fig. 117.—Wedge Cramp.
Fig. 118.—Dog, Round Section.
CRAMPING FLOOR BOARDS.
Floor boards are commonly cramped or tightened up by means of “dogs,” of which two forms are shown respectively by Figs. 118 and 119. The boards being already close together, the dog is inserted across, that is, at a right angle to the line of joint, one point being in one board and one in the other. The further in the dog is hammered, the closer are the boards cramped together. Floor boards can be tightened up without the aid of a floor dog by the method shown at Fig. 120. The board next the wall should be well secured to the joists, and then three or four boards can be laid down and tightened up by means of wedges, as shown. The following is the method of procedure:—Place a piece of quartering about 2 in. by 3 in. next to the floor board, as at C. Cut a wedge, and place it as at B; then nail down a piece of batten to the joists, as at A (both this and the wedge can be cut out of odd pieces of floor board). The wedge B should be driven with a large hammer or axe until the joints of the board are quite close.
Fig. 119.—Dog, Square Section.
Fig. 120.—Wedge Cramp for Floor Boards.
Fig. 121.—Circular Seat with Cut Cramping Pieces.
Fig. 122.—Circular Seat with Flexible Cramp.
Figs. 123 and 124.—Wood Horn of Flexible Cramp.
CRAMPING CIRCULAR WORK.
There will now be explained away many of the difficulties in closing or cramping the joints