Any piston can be made to stick with the addition of gunk or a foreign body, as can any rotary valve.Arthur plays tuba wrote:I think it's the problem of quality:
Rotory valve horns has a minimum price of $2000
But piston valves can be in every price.
So the 'sticky pistons' are always cheap.
Have you ever heard of a Meinl Weston piston sticks?
Rotary valves are actually cheaper and easier to manufacture than pistons. Consider:
- All rotary valves on a tuba are basically the same unit; i.e. they're interchangeable. So instead of making 2 or 3 different designs (as on a piston horn), you need only make one. (Exception granted for graduated-bore instruments.)
- The amount of hand fitting and brazing on a piston is greater. Consider that the "knuckles" on both are hand-fitted and brazed, but that the ports in pistons must be fitted and brazed also.
- The whole valve assembly is more complicated to assemble in a piston-valved instrument., as it must be hard-brazed together, while in a rotary instrument, the indiividual valves are usually fitted together using nothing more than soft-soldered ferrules.