Original poster: "Garry Freemyer by way of Terry Fritz <twftesla-at-uswest-dot-net>" <garry-at-ndfc-dot-com> Nice easy way to build a toriod. I had tried making toriods using the duct material but failed. Yours is the first set of instructions I believe I could actually succeed in. Simple, quick and easy to replace incase the ducting gets dented. I think I shall try this myself. Thanks again!