Carbon Fiber instrument manufacture

[Rick Denney]

Bell damage would be my biggest concern and repairs would likely affect the sound because there would be thicker areas where the cracks are repaired.

This was a problem with brass, too, and the reason behind rolled bell rims and garlands. Fiberglass sousaphone bells endure more pain than any tuba for a grown-up, and they use a molded-in rim to add strength. Carbon would be much stronger here. It would certainly be stronger than brass, though if it failed it would be a more difficult repair, of course.

I wonder if the vacuum or pressure layups used for bicycles and airplanes are mainly to provide the appropriate strength density for a part of particular size. A tuba bell might not be quite as demanding. I do know people who have hand-laid CF bicycles, and successfully so.

Rick "who thinks it can ultimately be practical" Denney

[Chuck(G)]

As far as repair, if you design it properly, it might never need repair except in cases where the damage is so severe that you'd just replace it anyway. Even so, I suspect sanding it down and laying another layer of material and resin, as with fiberglass repair, would be possible.

Rick, your idea of damage and mine must be different. I'm talking about "stupid horn player trips and falls on the tuba", "tuba bounces out of truck bed and lands on freeway" and "tuba gets into the hands of middle school student who hates band" type of damage.

All of the above can be fixed in brass, but how would one fix a flattened bell in carbon fiber?

[jacojdm]

All of the above can be fixed in brass, but how would one fix a flattened bell in carbon fiber?

I think that the point he is making is that these kinds of things wouldn't happen with the carbon fiber. It'd either survive such incidents, or, it'd be damaged so badly, it'd need to be replaced.

[lgb&dtuba]

All of the above can be fixed in brass, but how would one fix a flattened bell in carbon fiber?

Unscrew the damaged bell, screw on a new one?

If they can mass produce PVC elbows, pipes and fittings it seems they could "mass produce" tuba components for this new type of tuba. Once you get away from the idea that each instrument is hand built then interchangeable parts are very feasible.

I realize that's a gross over simplification of the economics involved, but it does seem like some of these new materials could be utilized in a more mass produced and less expensive fashion.

Not good news for intrument repair folks, of course.

[Chuck(G)]

I realize that's a gross over simplification of the economics involved, but it does seem like some of these new materials could be utilized in a more mass produced and less expensive fashion.

Let's start with valve sections.

If you're going to go to mass-produced parts, then you'll have to simplify the number of models and configuration variations down to a handful, otherwise economy of scale won't apply.

So, does everyone here want to play a King 2341?

[lgb&dtuba]

I realize that's a gross over simplification of the economics involved, but it does seem like some of these new materials could be utilized in a more mass produced and less expensive fashion.

Let's start with valve sections.

If you're going to go to mass-produced parts, then you'll have to simplify the number of models and configuration variations down to a handful, otherwise economy of scale won't apply.

So, does everyone here want to play a King 2341?

Hmm, that's a larger stretch than mass producing all the major tubing in carbon fiber and making those parts interchangeable between horns of presumably the same manufacturer and model. I wasn't stretching the idea to include interchangeability across manufacturers.

I was thinking more along the lines of the bell is crushed, so what? Unscrew it, order a prepacement, screw it back together. Bottom bow cracked? Take it apart, replace the bow with a new one, put it all back together. No soldering. No dent removal. No polishing, buffing, or lacquering. No more trouble than replacing a mouthpiece.

OTOH, with standardization and interchangeability of all the various parts (in a single model or series) there could even be an after market set of parts. Different materials. Different colors. Different bell sizes. Bell up. Bell front. Many custom possibilites for frankenhorns.

Want 5 rotors instead of 4? Swap out the valve section as a unit. Reuse the rest of the tuba. Many possibilites.

I had a Jupiter euph that the valve section was designed to be removable. Really made cleaning easy. Just a small wrench to loosen the bracing. Didn't even need a snake to clean it. Think of the advantages of being able to clean the valve section separately. Or working on the sections of the horn without the valve section being attached.

I never looked into it, but replacing that whole valve assembly would have been trivial. No more effort than putting it back together after cleaning it. If the rest of the horn had been made out of carbon fiber it would be exactly like what we've been discussing.

[Chuck(G)]

Mark's right--spinning is one of the cheapest ways to form something like a bell shape out of a hunk of metal. I suppose that CNC spinning of 201 stainless steel might be cheaper, but I don't know if the world is ready for stainless steel tubas yet.

[Rick Denney]

I was also informed that fiberglass sousaphones were not any cheaper to manufacture than all brass instruments. I would think that carbon fiber, although it's sexy and hip material these days would be a very expensive way to make a tuba.

I didn't realize that being cheaper was a requirement. Carbon composite bicycles certainly are not cheaper than their metal counterparts, except for titanium. And most of the cost of that is in the tooling necessary to weld it without ruining it.

I would think a clamp system count be deviced to replace the main bottom-bow ferrules, instead of more traditional joints. I'm thinking something like a band clamp used on high-end exhaust pipes, but a little nicer looking and a little more tailored to the application.

The point of CF would not be to make it cheaper--tubas are already cheap compared to many instruments--but rather to make it lighter and more durable.

There are a couple of repaired cracks on my fiberglass Martin, and the braces were reglued with something not really strong enough (I will be fixing that), but despite 45 years of regular use and an old story of serious shipping damage it's still basically sound and undented.

Brass is easy. That's why it was used 150 years ago and why it is still used. It's the labor that drives up the cost of a tuba (not to be confused with the price). CF layups would require just as much labor, at least at first. But it would be possible for people without the ability to spin bells to experiment with hand layups. Different skills that would be easier in some ways but maybe harder in others.

Rick "noting the downward price pressure on CF bicycles" Denney