i just tried tb3 and it didnt stick to some 5 oz leather i had. im trying now by dampening the skins first then applying to a piece of sized leather with tb3 in theory this may work better, since tb3 is water dilutable while its still liquid, the skin may take some of it in along with the small amount of water. ill post results. otherwise i can try spray contact cement, and superglue, although i know superglue will make skins transparent to some degree and they work best over darker colors.