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My Stpetersburg 202 and i have had a few problems through are 8 months we've been playing. First, Mr. Fedderly discovered that the reason no spit came out the spit valve, was because a hole had not been drilled.

But most recently, i purchased a Shilke Helleberg mp, and i like it, the only problem is it sites out a lot from my tuba. My question is for anyone who has had a procedure done on the bore of their horn. About how much did it cost? And were there any negative results?

Actually, I believe a hand reamer in the Morse taper is used, as a drill would take a lot of material really quickly. It should be a straightforward job with a competent tech. If the spit valve had not been drilled until you looked into it, it sounds like the basic reaming on the receiver has not been done either.

iiipopes wrote:Actually, I believe a hand reamer in the Morse taper is used,...

It should be a Jarno taper.... EXACTLY .050" of taper per inch. Morse tapers vary a dab depending on the taper number. Enlarging a receiver by any signifant amount is not an easy task with a hand reamer. It would be just as easy to just replace the receiver. It's unfortunate that there aren't any PRECISE industry standards for mouthpiece shanks and receivers. Often different mouthpieces engage deeper or shallower. There have been many discussions regarding different shank sizes and 'the gap'.

Dan - Thanks.