Tension on Rotary springs

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Tundratubast
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Tension on Rotary springs

Post by Tundratubast »

Does anybody know the pounds load on a typical rotary tuba. I need it for my hand therapy.
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Re: Tension on Rotary springs

Post by windmill »

I am not sure of the actual tension, but I have a rotary tension problem that is currently being fixed. I have noticed that the tension does seem to vary noticeably from horn to horn. Even on new ones.

I bought a used 188 about 6 months ago. When I play tested it I noticed the rotary tension on the springs was high. A careful look at the springs revealed that someone had been messing with the spring tension. The wire had been bent out of shape and then wrapped around to increase the tension. Matt Walters finally has the tuba now (thanks Matt) and he is replacing the springs. He had me depress the rotary valves on a few show room horns to see which one had the tension feel that I preferred (lighter better for me). He will also put in new bumpers (corks).

It's hard to imagine why someone would intentionally (intensionally?) make a tuba harder to play. Operating the valves under that kind of tension just set up a big deal of tension in my right shoulder. very unhealthy. Maybe the increased tension gave a previous owner a feeling of control? maybe it was done to compensate for the worn bumpers? who knows. I can't wait to get the tuba back from Matt. He is a miracle worker.

for your question, perhaps you could take one of those luggage scales and set it up so its pulling on the flapper? I'm guessing it's about 1-2 lbs of pressure. I hope your therapy is resolved.

Steve
Mirafone 188 2003
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