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A Kelpie.

Dang, Joe! You get ALL the fun stuff. Is this one of those Chinese Miraphone 1291 copies? I'm really puzzled by the port witness mark on the 3rd piston from the left.

I agree that the venting was ill performed, but not critically wrong. Just not right.

I'm no expert, but I seem to remember many of the budget Chinese brass offering "cupronickel" (copper-nickel) valves and slides. Cupronickel is very similar to nickel-silver (which actually has no silver in it, but is in fact brass-nickel). I'm thinking cupronickel is fine for leadpipes and the more stationary slides, but maybe not so much for piston valves?

bloke wrote:
I'm just surprised to see that someone in the current era is selling a piston C tuba - which appears to feature raw/unplated nickel silver pistons - for a price as high as what this repair customer of mine reportedly paid.

I know exactly which vendor/brand you are talking about -- their pricing seems to be creeping up well into the 'higher-grade' Chinese brass, new Cerveny/St. Pete, and good-condition used German brass pricing Their aggressive marketing and hype does not impress me, but a lot of ppl seem to be enamored with their products

Interesting., pretty sure it is raw nickel-silver. Good part is that it can be upgraded in the future with nickel plate and honed to size (rebuilt) resulting in really decent action, whereas the stainless steel valves are destined for a one-way trip to the scrap pile. The horn may have limitations but in a different view, the "cheaper" valve construction does have a silver lining to its story.

D.C. Oberloh
Oberloh Woodwind and Brass Works

I admit that, being a bit of "an old timer" and not really active in the repair game now, I have never had to deal with stainless pistons.
What Daniel O. just said makes me wonder "why?" stainless pistons instead of proven monel (nickle silver or as often called, cupro nickle.

Question -- do some Chinese rotary tubas, then, have surprises like this lurking in the rotors? The linkages are usually the problem area, but seeing as how rotors are so infrequently removed... could there be stuff like this waiting to be discovered?

I won't argue over a couple percent of other metals content.

The more important consideration is the "fit and finish" of the pistons and casings. Either very good or craptastic valve sets can be made from most any material.

A comparison from over 50 years ago could be a Taiwanese made trumpet with "close enough for jazz" clearances of mass produced and not individually honed and fitted valve sets and a Schilke where every valve piston and casing was individually fitted with monel being the piston material. The old S#iT and Shinola comparison seems about right.

What model Wessex is this?

I’m left with a few questions after reading this thread:

- As a buyer, how would someone be able to tell what the pistons were made of prior to sale?

- What is the impact of having raw nickel silver pistons to the instrument over time? I could see sluggish valve action being a factor, are there any others? And, could these effects be mitigated by simply wiping off the piston prior to applying oil? I could, in my limited but morally damaged mind, see this being a bigger factor for silver plated instruments versus a raw / lacquered brass version.

- Ideally, if I walked over and examined a German tuba what kind of piston would I most likely find?

- These kind of stories seem typical for instruments that arrive from The People’s Republic- is that a fair statement?

I once did maintenance work on an Allora (Yamaha YEP-321 copy) euph for a colleague of mine. I noticed the pistons were tarnished; one of them was sticking badly. I had to carefully clean and shine them up and they started moving fine. Told the guy to please oil them every once in a while -- the euph had been sitting stored away for a while. I'm thinking the pistons on that Allora were made the same as the tuba pistons in this thread, either nickel-silver or cupronickel.

Also noticed the same thing with a budget Chinese F-trigger trombone I bought several years ago. Pretty sure the slide is cupronickel as it tarnishes more easily than 'regular' slides, and still has that grayish-silver color to it. That trombone actually has a really nice sound and plays well, even though the linkage is crappy. The slide is OK when I wipe it down and re-lubricate it every once in a while.

While we are talking about valves and slides and the materials they are made from......
The rotors on my old pre-WW2 Kaiser BBb are a light, dull silver-gray color. They do not appear to tarnish, and they (and the old clockspring/linkage) are very fast & light. I dunno what alloy they are for sure
On my Meinl CC, the rotors are a deep brass color. I think I read here that most 'modern' (last few decades) German rotors are actually made of bronze

I'm *really* glad I bought a Miraphone.

kingrob76 wrote: - As a buyer, how would someone be able to tell what the pistons were made of prior to sale?

If you know someone in the junk recycling business, you might be able to bribe them to come along and get a reading on their XRF gun (hand-held x-ray fluorescence diffraction analysis.) The equipment costs as much as a tuba, and judging by the fact that no one will say how much they cost to rent, that's too expensive too, but people have them, and it's a foolproof way to find out the atomic composition of a surface, and thus exactly what alloy or plating metal you have.

There are various copper-nickel alloys, with various properties. Along with the percentage of nickel, there could be small amounts of other elements like iron, manganese, etc., usually for strength or extra corrosion resistance. I gather that if you found the dread nickel silver, you would see a significant amount of zinc, like 20%. Cupronickel would likely have none. (By the way, the story with copper nickel alloys and China, you ask? Well, they invented it! German nickel silver was an attempt to copy the alloy found in metal articles imported from China.)

While you have access to that XRF gun, try to get a look at some of the bells from yesteryear - any extra iron in the York bells? Kanstul and Reynolds bells that are advertised as bronze, really Cu and Sn? And what's the coating on those little silver balls that are used for cake decoration?

There’s so much misinformation in this thread I don’t even know where to start.

First off the pistons are made of stainless steel. I’ve been on the floor there, handled the parts myself, and have even seen the stainless bodies heat treated before they are assembled with all the brass ports and top/bottom.

Trying to determine what metal is used by color is literally the WORST way to figure out the grades of metal. Adding even 0.04% of an alloying metal can change the color of a metal. How a metal is worked, heat treated, or polished can change its visual look. My sellsmanberger and Parker mouthpieces even appear to have a slightly different color, yet the blanks are made from the same place from the same steel. Parker just does more with the polishing.

“Stainless steel” isn’t a single metal but a range of metals. Much like “tool steel” is not a single metal as well. There are many grades of stainless that all have different uses, looks, and capabilities. Some can be heat treated while some can’t. Some are much more difficult to machine than others. Not all manufacturers use the same grade.

Stainless steel also doesn’t mean “corrosion proof” but more corrosion resistant. Stainless isn’t immune to the nasty things we throw at it. I’ve even had to clean rust from my blokepiece solo a few times. Does that mean it’s made from some inferior metal? Nope, more that I should clean it more often and be more mindful of where I set it down in my shop.

Speaking of cleaning, when I got to the USAREUR band I was issued a PT606 tuba to use. The valves were quite stuck and when I got them out they looked just like the dirty valves in the first picture. The tuba also has a good bit of silver plate wear so it was clearly played dirty, never cleaned and possibly very rarely oiled. I’ve also seen much worse then that and I’m pretty sure anyone here who’s done repair work has also seen much worse valves.

To address the comment about different materials being used for valves working this is very true. If you look outside the music industry you’ll see many materials used like steel, bronze, brass, aluminum. Many older lathes even used cast iron plain bearings and they are still running after 70+ years. Many materials can be used, though some are better than others (brass is NOT a great one but is what has been used in our industry for a long time).

On my next trip to the factory I’ll make a bunch of videos showing a lot of this. I’ll try to dymistify as much as I can for you all. Time to start a YouTube channel!

Oh and the venting. Putting the hole up higher allows venting to happen longer during the stroke of the valve, during the “half valve” time. Putting it lower removed the venting earlier, making the blow through the half valve inconsistent. While more care must be taken to drip the hole so as to not go too high it does have a reason and an effect. Most people drill in the middle because A) it’s an easy coordinate to copy paste on the cnc or B) less chance of messing up a customers valve. Just because something has been done a certain way doesn’t mean it’s the best way. Innovation and trying to make things better is something I think the musical instrument production field needs right now.

It’s best that if you have a question with any manufacturers goods that you ask the manufacturer directly, regardless if a tuba or a car or anything else. They will be able to give you the answers you seek.

I will add to Chuck Nickles’ detailed post above by pointing out that there is the most sophisticated equipment available at the factory to measure metal composition and all metal used in production of Wessex is subjected to specto-chemical tests - so there is never any doubt about the metal composition and the valves being stainless steel.

As far as the deposit, that is some chemical reaction that can happen to any brand of tuba, due to the mixture of metals, oils used, acidity in the players saliva or what they may drink before playing. I know of a top professional with the most expensive tuba in the world having exactly this problems. He had to change valve oil to solve.

Rivercity Tuba wrote:What model Wessex is this?

I believe it would be their Wyvern. (A CC between 5&6k with kelpies on the buttons )

While other models expressly state that the valves are stainless, on the Wessex web site, this one does not.

Melton tubas are said to have “perinet” steel valves, whatever those are...

This is one of the many topics that I have always been puzzled by:

Here in the 21st century our experts seem to be agreed that stainless steel pistons are preferable because the steel doesn't wear off of the piston, but back in 1980 when I bought my tuba there were experts warning that stainless steel was too hard for pistons, and would wear away the valve casings. More specifically, I can remember at least one article that predicted that the assymetrical pattern of valve ports would cause a triangular wear pattern, making the pistons a sloppy fit. It also predicted that this damage would not be economically repairable, so the instruments would have to be scrapped.

At that time, conventional wisdom appeared to be agreed that valves would last much longer if the surface was a "bearing metal" that would "give" (wear ?, flow ?) slightly, allowing it to conform with the casings.

I can remember seeing serious minded arguments offered in favour of "Solbron" (solder/bronze) and "Silbron" (silver-solder/bronze) as alternatives, both for Monel metal (described as an expensive naturally-occurring alloy, becoming scarce) and also for stainless steel. I always assumed that these were bronze pistons with a sacrificial coating of solder ?

We are now forty years on and I don't seem to be hearing any horror stories about excessive wear caused by stainless steel valves (even the awful warnings about red-rot caused by ammonia-based glass cleaners seem to have faded out). Can we sound the all-clear, or is there a piston apocalypse looming just beyond the time horizon ?

MikeW wrote:We are now forty years on and I don't seem to be hearing any horror stories about excessive wear caused by stainless steel valves (even the awful warnings about red-rot caused by ammonia-based glass cleaners seem to have faded out). Can we sound the all-clear, or is there a piston apocalypse looming just beyond the time horizon ?

I think it just shows that we don't practice enough.