Doc, Read Jim's post again:
I also only use the first 1" of the full sized kit body tube, drill full with the kit size to about 1 1/8 depth then the full length with the 7 MM to 2 7/8". I epoxy the full length tube in the body, then trim the excess tube off after turning the finished body on the mandrel. This gives me more options for body shapes, leaving more "meat" on the blank to thin out...
He could be using the Arizona mandrel, or a pin chuck either one. By gluing in the full tube, he can use a the whole mandrel to hold the blank, and then part the tube off when he's done. Pretty clever idea, and I wouldn't have caught it myself if you hadn't asked him. Thanks!