I know all about making bellows and my advice is to go to someone who makes them.The main component is a collapsible wooden jig to make them on.I have had a go and Geoff Crabb was there when I took them in.It caused great amusement and discussion.I have a nice duet that requires a set of bellows and I shall farm it out to probably Dave Prebble a member of C.net who will make something that will last a lifetime.
Al