Weird conversion question

[MaryAnn]

Ok, not a conversion but an "ease of use" question. We engineers think of all kinds of weird stuff all the time. I think it's genetic.

Anyhoo, let's say a person likes the response of a particular piston tuba but has hands too small / weak to reach the pistons well enough to play it. Has anyone thought of replacing the buttons with "troughs" that would fit fingers "as if" they were paddles, sort of more or less, understanding that they still have to go straight up and down but with more finger to do it with. With paddles, I can use a lot more of my finger to move the rotor, and for me that is is a whole lot easier than trying to play with just a finger tip like I have to do on pistons. Even a euph is beyond me physically to play fast. So the trough idea.

Anybody think this is not totally insane?

[windshieldbug]

My first question would be: could the bore of the tuba be made small enough so that small hands could reach each "trough" without having the pistons be too far apart...

[Donn]

understanding that they still have to go straight up and down but with more finger to do it with.

I think I get what you're talking about here -- is it possible that rotor requires a little more force at the beginning, and the way your finger rests on the paddle, that initial push involves more of the finger, though at the follow-through end of the paddle travel you'd be more out on your finger tips?

Sure can't think of any practical way to do that.

[MaryAnn]

Bug, troughs could be angled such that the paths were closer together. I understand the "must be up and down" part. Just wondering, on the engineering level, how this could be done. My euph is the typical 3+1 but I can't play it fast. I can play my horn fast though, and I never had any trouble with rotor tubas in terms of the part of me doing the valves.

[Dan Schultz]

I built some custom finger buttons that were basically rings/troughs. A fellow had a stroke and was having difficulty keep his fingers on the buttons. It worked out fine and kept him going until he made enough of a recovery to go back to conventional fingerbuttons.

I've given some thought to building paddles that would operate fingerbuttons that can be placed just about anywhere on the horn. There's no reason why pistons couldn't be pulled down from the bottom instead of being pushed down from the top.

[windshieldbug]

There's no reason why pistons couldn't be pulled down from the bottom instead of being pushed down from the top.

Kinda like a Vienna Valve Trombone...

[MaryAnn]

You're a smart dude, Dan!

[pittbassdaddy]

Would having the valve stems offset like the short action Conn valves accomplish what you are looking for?
This would necessitate modifying the pistons and having new valve caps fabricated.

[Rick Denney]

I needed a paddle for the fourth valve on my York Master, and a fellow on TubaEuph (I think) made one for me. It places the finger pad about 3/4" from the center of the valve (as shown below). If placed on all three valves, they could be angled to bring them closer together.



The engineering question is an interesting one, and I thought about it at the time (which was a long time ago). But let's think about it again. If the valve on a compensating euphonium is five inches long, as it approximately is on my Besson, then force applied 3/4" off center will create a lateral load 15% of that force at the ends of the valve bodies. If that's what makes a valve stick and wear excessively then it's dirty, dry or both.

(Note that pushing straight down on an offset button is not at all the same thing as pushing sideways on the edge of a button, as many students are cautioned against doing. That applies lateral force directly, instead of just the lateral component of a force couple. So, an offset paddle is the only reasonable solution to fingers being too short for a valve placement.)

But that won't do anything to reduce the throw of the valve, which has to be the diameter of the ports plus the width of the sealing surface between the ports. Rotary valve mechanisms are designed to reduce the mechanical advantage slightly, so that the paddle moves a shorter distance. Of course, that requires slightly higher force, but rotors are heavy and additional force is required anyway to accelerate them from a stop.

Rick "who can provide closer pictures if needed" Denney

[MaryAnn]

That looks like an elegant solution (I know engineers like that word "elegant.") I have no such instrument to try anything on at present, hence the "academic" nature of the question, but have wondered what solutions might be out there.

[Art Hovey]

I did something like that on some tubas several years ago, and I am still using two of them:

http://www.galvanizedjazz.com/tuba/valv ... nders.html" target="_blank" target="_blank" target="_blank