They also use just plain water to stiffen leather, but not sure how it will work on older leatherI know of a couple of people around here that make and sell leather masks (2-3 oz leather) that stiffen them by soaking the masks in a mixture of warm water and Elmer's (white) glue - about 1/4 cup or so for 2-3 gallons - before molding. They swear by that instead of commercial leather stiffeners.
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