Fig. 138.
Fig. 139.
[Fig. 140] illustrates three kinds of bar clamps such as are used for clamping wide frames and boards.
Fig. 140.
[Fig. 141] illustrates a simple form of clamp which can be made by the student himself. Two wedges to each clamp, driven in with the hammer, supply the necessary pressure. Whenever finished surfaces are to be clamped, blocks of wood must be placed between them and the clamp jaws to prevent their being marred.
Fig. 141.