Posted by Lee Stofer on February 11, 2004 at 09:08:30:
In Reply to: Piston Valve Spring Tension posted by Todd Morgan on February 11, 2004 at 00:14:26:
The valve spring tension needs to be enough to allow quick, clean playing, but not enough to wear out your hands. I have suffered hand injuries from over-use while playing string bass and a large piston-valve tuba.
I would suggest using extreme caution in stretching springs. In my shop, I keep a wide variety of springs, felts and corks, and try to find the best set-up for each instrument. On many instruments, I now use Yamaha springs if applicable, for although they are more expensive, they are worth it because of the quiet, clean valve action that they make possible.
On rotor and piston horns alike, I suggest adjusting the spring tension only when the instrument is freshly cleaned. I've seen a number of people violate the springs on their rotary tubas when what they really needed was a cleaning to restore valve action.
Lee Stofer