Help with Shugart SA801 8" floppy with 230v 50 cycle

Hi I agree that the bottom part usually doesn't even touch the belt but the part of the belt that is not stretched over the crown is closer to the same stretch as would be on the other pulley. I would tend to think the closest to the shaft that is just touching the pulley is closer to the speed of the belt than the stretched part over the crown. Depending on how elastic the belt was, this could be quite different than the top of the crown. Still, the belt would need to have a small amount of stretch length wise to force it over the crown. This would mean that the effective diameter was closer to the diameter where the belt was just touching and not the crown. As for why it stays on, that is simple. First, as anyone who has tried to put a belt on a moving pulley will tell you, the belt will no walk up a tappered pully. To get the crown to work, one needs to get some amount over the top. It will then center. Lets look at what happens as the belt is off center. The side that has the wider distance from the crown will be stertched less and ride lower on the pulley. The narrower side will ride higher. Because it rides higher, it will have more tension than the wider side. This will pull it back to the center. If it gets pulled too far uneven, there won't be enough tension on the narrow side to pull it back and the belt will slip off. This effect can also happen if the load is too large. These effects can be demonstrated on disk drives. Dwight _________________________________________________________________ Get more done, have more fun, and stay more connected with Windows Mobile?. http://clk.atdmt.com/MRT/go/119642556/direct/01/