When the leather is to be modelled in high relief, the design should be well separated from the background in the cutting process. The incision should also be deep when the outline is to be accentuated afterwards with a
tool called an “opener” (Fig. 9) to produce an effect like the leading in stained glass.
Should it be desired to raise and turn up the edge of the leather to simulate a leaf, petal, or piece of ribbon detached from the background, the knife must be held slanting, as in Fig. 8, so as to make an almost horizontal cut.
FIG. 6, FIG. 7.—INCISING KNIFE HELD LIKE A GRAVER AND PUSHED FORWARD
However thick the leather may be, it is important that two lines should never be cut quite up to the point of intersection. For example, in cutting the outline of a leaf, the points of the indentations should be left uncut to avoid the tendency of the part within the angle to project and turn back. Sufficient impression can be
obtained with the modelling tool to give a finished effect to these points.
