Other methods to solve the problem of sheepskin hardening:

Arsenic trioxide, indica rice flour and water are dissolved to prepare a solution.

Spread the wool leather board on the wooden box, spray cold water to make the leather board wet first, then dip it in the prepared solution with a brush and brush it evenly on the leather board.

After brushing, let it stand for two or three hours, then brush it for the second time, and repeat it for five times until the solution soaks through the leather board.

After drying, rub it evenly, and the leather board will become soft and elastic again.