Kevin,
Great website, thanks for sharing it.
I really enjoyed seeing the pictures and reading about the Incredible Double Bell Euphonium that you made from a Willson/Marzan euph. One question: could you describe the notching process? i.e. I have often wondered how the notches I see in the bell seams of my horns were produced, why they are part of the bell-forming process, and do they interlock or do they overlap?
You asked for suggestions for products: how about tubing in sizes to fit the needs of low brass. The largest size I saw listed might work for a British Baritone, but thats about it.
-Dave