[Dodge]

Bruce,
As Thomas confirmed, TSP does clean the fat. After I boiled in plain water for 2 hours, there was still greasy marrow on the inside of the bones and even some gristle still attached to the outside. You usually have to split bones anyway as a typical leg bone is usually too big for anything but the biggest knives and swords, so this opens them up to the marrow, and TSP solution takes care of it. It also will dissolve the bone if you boil too long and use too strong a mix. Even at the 1:64 mix I used, there was a white chalky coat on all the bone. It scraped and sanded of easily, however. Again, take caution of dust when working with bone!