Mechanical softening of leather. Done by hand by pulling skins over a moon shaped knife, but mostly by machines of which tow types are common. The old "grab" staker with crocodile jaws which come together at a point where the operator offers the hide or skin and pulls the leather away from him while he restrains it carefully and the vibrating through feed machine invented in Czechoslovakia in the sixties. The former is more precise, but is also more labour intensive and skilled, while if not used carefully will lead to tearing and loss of area.
Using a tool with a canoe-paddle shaped edge to help soften the hide. The tool is often embedded in the ground, in a vice, or some other contraption so that you can work the hide over it. The edge should be distinct but not actually sharp.
Mechanical softening of leather by the action of a very large number of rapidly oscillating, overlapping fingers or pins while being carried on a conveyor belt.