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Art Hovey wrote:Two questions for the pros:

(1) A friend of mine who works in a shop specializing in trumpets and trombones wrote: "Is there any chance you've worked on B&S clockspring valves? We' ve got a Symphoni model in the shop from the 1970's and can't get the casings opened to change the springs."

Those casings should just be pressed together. Once the housing is off the shaft, they should be able to be driven apart. The tech might be able to reuse the clockspring if just the end is broken off. Anneal the end of the spring so it can be bent without breaking it and just put in back in.

(2) A tuba student has a nice new Jupiter CC tuba with 4 pistons and one rotary valve. The 5th valve is operated by a right thumb paddle which pushes a long rod straight down. He would like to raise the paddle a bit, and it looks as if the rod's length is adjustable. There are two knurled nuts on the rod, and both of them are only finger-tight. How does one lengthen the rod? (I hesitate to monkey around with it as I would with a junk tuba.)

I don't think that rod is a turnbuckle. Take one rod end loose and unscrew things a bit and then snug the thrumbscrews back down.

I can remember when the Jupiter C was a rocket.

sailn2ba wrote:Would the clocksprings on a Miraphone 185 (circa 1960, I think) be dis- and re-assembled the same way?

Lee Stofer wrote:On a B & S Symphonie F tuba with trommelfederdrueckwerk (clockwork springs), one should find that each valve lever has its own axle shaft. So, I set a lever assembly on its side on top of the vise, with the vise open-enough that the nickel-silver edge of the spring housing rests firmly on the vise, but there is an opening where the brass side of the housing can come out. Then, tapping with a rawhide mallet, I tap on the steel shaft axle. Inside the spring housing, the axle shaft has a small brass cylinder attached, which is where the spring attaches to the axle, but also serves as a driver to push out the axle housing side cover. If one side does not want to budge, turn it over and try the other side. Normally one side moves easier than the other, and how tightly these covers are fit onto a lever can vary greatly. And, there are typically alignment marks on the brass cover, to get it properly aligned when reassembling it.

As for the Jupiter CC tuba, the knurled nuts adjacent to the metal ball links are only meant to be locknuts, so that the ball link can be centered, then secured in place by tightening the locknut against it. The options for changing the 5th lever height include carefully (!) bending the lever with key bending pliers, or fabricating a longer (in this case) linkage rod.

You remember when the Jupiter C was a rocket? Yes, you're dating yourself a bit, but that's OK. I have very vague memories of John Glenn orbiting the Earth when I was 3 years old. We watched the launch on TV, then, it being a sunny morning, I ran outside to watch for him. I saw a high-altitude jet trail, and was convinced that I had seen John Glenn and his spaceship go by..........................