Not sure I follow the last couple comments on this one, but what I do is use hardwood ashes.
a 5 gallon bucket, filled about halfway with sifted ashes (to remove the big charcoal chunks), add about a gallon and a half of water, stir it up, let it settle, and float an egg in it. The egg should float upright with an exposed area about the diameter of a half dollar, like this:
if the egg floats like this, you're ready. If it sinks, add a little more ashes, if it floats and rolls over, add a little water. Put on gloves. This is the same thing as lye solution.
dunk your fleshed hide in it, stir it around to make sure all surfaces are coated, put a rock on top so it doesn't float, and wait. Check it every day, maybe twice a day, more if the weather is warmer. When the hair will rub off with your finger, it's ready to be scraped, washed, whatever, depending on what you are making. Rawhide or grain leather: just rub the hair off; Buckskin: get your bucket of elbow grease and drawknife.
I wetscrape because I like the way it's self regulating. Once the hide is ready, I take the hair and grain off all in one fell swoop (well, sometimes two or three). I am of the understanding that dry scrape is tedious, and time consuming. Steve Edholm says in his book that letting them enter a certain stage of decomposition helps loosen the grain without using ashes, but the book is about wet scrape.
Ben Kirkland, who teaches braintanning, cannot tell the difference in my wet scrape and someone else's dry scrape (except that mine has no washboarding).
To be master of any branch of knowledge, you must master those which lie next to it; and thus to know anything you must know all. -Oliver Wendell Holmes, Jr.