OK, I finally clicked on this thread after how many months? The lap top I am using sits on top of a treadle sewing machine. I have unhooked the belt and I "treadle" while I type. I have changed the belt and have had my dad adjust it so many times that I am embarrassed to ask him again and it is still too loose. I cannot use it for sewing and it is so frustrating. I love this machine. Any suggestions?