I am on my 3rd clipper. 2 Oster A5's and one heavy duty Andis with 2 speeds. My dog is an American Eskimo (aka: Spitz or kindof a Miniature Samoyed). I just can't find a clipper that will go thru that undercoat layer. It's too thick for anything I've tried. There's got to be some clipper out there that can go thru that like butter. Help!