When bucking a hide in wood-ashes, lye, or lime, it is important that the solution remain relatively cool when hides are soaking. Hides in plain water will weaken if they get too hot, but this temperature seems to be lower when hides are soaked in alkali. We've experienced this, and so has Bob Kitch. Soak your hides in the shade whenever possible and if they must be in the summer sun, beware of dark containers. Pumicing your hides toward the end of the softening process will give your hides a softer surface texture than anything we know of.
Pumice is also handy for easily removing any missed grain, membrane, crust or shallow stains.
Pumice is used just like a sanding block, but it has the advantage of never getting dull. The hide did not seem to brain and soften any more easily, which is the point of pre-smoking, but that didn't bother me because I knew I haven't had any proper instruction in that method anyway. Normally that hair would have been slipping in two to three days. There are two challenges with furs. One is trying to get them soft, before the hair starts to slip out.