I have to share this treatment I discovered to deal with thick skin on hands and feet. I went to a cheap dollar store (Dollar Tree-in United States) and found a foot file. One side is a smooth file and the other has a rough metal texture similar to a cheese grater. I used it on my hands and feet right after taking a shower and you would not believe how much skin came off. My hands and feet felt smooth, something that's hard to come by in my case. This file literally grates the skin off. It is much better than my trusty ol' pumice stone. These files are easy to come by, they are sold in nearly every drug store in the section for foot care or cosmetics. The one I got cost $1.00, so you really don't have to pay too much to get these kind of results.
Let me know if you try it. If you already use it, how much filing is too much?