Here's my method of turning and attaching collars to hollow forms. Like most other things, there's lots of ways to do this, but I've found this to be the easiest.
1. You can make the opening a little bigger than you normally would. Square up the shoulders of the opening.
collar1.jpg
2. Roughly round the collar stock on the bandsaw. Jam against the face of the chuck jaws with the tailstock.
collar2.jpg
3.Use a parting tool to form a tenon the thickness of the HF wall to fit inside the opening of the HF. Undercut the edge of the rim to make sure the perimeter of the collar sits flush with the body of the HF.
collar3.jpg
4. Lightly chamfer the lower edge of the collar.
collar4.jpg
5. Check the fit of the collar in the HF (Sorry, that pic was too blurry) and reverse on chuck, holding the tenon with the jaws. I have used a glue block and turned it down to the diameter of the tenon, then glue the collar onto it with thick CA glue. Using the chuck jaws is much simpler.
collar5.jpg
Cont.
