Hacking knife

They are strongly constructed with a single-sided straight edge, resembling a small cleaver.

Unusually for an axe, this back edge is intended to be hit with a steel hammer, not a wooden mallet or club.

The hacking knife is used to chop out old putty before replacing glass panes.

The side knife may be used as a light froe, for splitting small billets of wood.

Unlike a froe's extended handle, the side knife does not permit twisting to lever the split open and so it must be driven through all the way.

Glazing work, removing old putty before re-glazing
Beginning the split
Cleaving with the side knife
Cleaving complete, with a split billet