61, or across it, Fig.

62.
The bending aside of the shaving will require less force the smaller the taper of the wedge.

On the other hand, the wedge must be strong enough to sustain the bending resistance and also to support the cutting edge.

In other words, the more acute the cutting edge, the easier the work, and hence the wedge is made as thin as is consistent with strength.

This varies all the way from hollow ground razors to cold-chisels.