As the owner of one of these, I can identify several weakness in the design that would cause problems with school gorillas. One is that the attachments of the braces to the fiberglass bows was done using fiberglass resin, probably plain old polyurethane resin. If they had used epoxy, they wouldn't have all let go on mine.
The other weakness is the bell edge, as your pictures shows. It needs some sort of reinforcement to prevent cracks in the fiberglass binder.
Also, I suspect those slick Martin thumbscrew-tightened mouthpipe adjustment bits are about as easily lost as King sousaphone tuning bits, but more difficult to replace.
I disagree with Bloke about the fourth valve, especially if the alternative is a three-valve compensator. With compensation, the pistons are a couple of inches longer, and that makes for an even more fragile assembly when (not if) it is dropped, and that much more opportunity for the casing to get tweaked when (not if) the tuba is dropped. It's not that hard to route fourth-valve tubing in a way that allows it some protection. But fourth valve branches were often added as an upgrade, and so were designed to be easy to install after the other three valve branches have already been assembled (or at least they were designed around the other three branches). This is especially true with old budget tubas that routinely came with three valves.
There are some design features all tubas should have, but that they have never had. One is, like saxophones, guard covers over exposed tuning slides with enough crush space to absorb the usual bumps. Another is handles. And some braces that instead of using the valve tubes as the connecting nodes, extend from outer branch to outer branch all the way across the tuba so that a blow to the outer branch doesn't have to be absorbed by the valve tubing. And then a heavy brass ring around outer branches at key brace attachment points, to prevent the tubing itself from caving in when the brace is overloaded (or when the tuba falls over). These features would add some weight, but then other things could be a bit lighter. And those school kids need the exercise.
But one thing that would reduce the damage considerably would be parents being required to place a deposit on the instruments the kid borrows from the school, the remainder of which is returned after the abuse-related repairs are paid for. It would never be big enough for real accident, but it would cover a lot of the usual carelessness. I'm thinking $500 for tubas. Or make fiberglass sousaphones available for only a $200 deposit, for the impecunious. Would that kill band programs? Maybe, but school districts seem to be killing band programs anyway.
As to the use of Chinese instruments, that's a given. Nobody is making alternatives for student use, and even Yamaha student tubas are almost assuredly made in China.
Rick "insurance would be too expensive because the risk is too high" Denney
