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We are debating whether to go to (a particular alloy of) bronze to use to fabricate the screw shanks (ONLY...not the cups nor the rims).

The particular alloy that we're considering is really similar to stainless steel in it's properties (regarding resistance to being bent/dented/etc.)

We're also thinking that (as far as copper/silver/whatever allergies are concerned) the shank is far enough back for (hopefully) effects to be negligible or nonexistent.

This material would be easier to machine, and (as making shanks calls for the use of boring bars) fewer passes, less tool wear, and quicker production. (This could result in all three parts - rims/shanks/cups - being more available with less backlog, as the STAINLESS STEEL shanks - in particular - require quite a few machining operations.)

Additionally (though no promises) as this particular (and others) alloy of bronze is also particularly good for fabricating bearings, the cup-shank threads might work a wee bit smoother, and might (after months) be a wee bit easier to "free" from each other.

The cups would continue to be fabricated of stainless steel, and the rims would continue to be fabricated of stainless steel or of titanium-coated (usually: gold tone) stainless steel.

We're also thinking (sorta like someone else who makes their 3-piece mouthpieces of yellow brass) of NOT plating the bronze shanks - particularly as they tend to patinate so nicely.

...so attached is a simple poll for (please) those who've purchased our mouthpieces in the past - and/or (more importantly) those who've been considering purchasing them in the future.

oh yeah...
We have a considerable number of shank "blanks" remaining (to finish into specific models), so this would not be right away.

Just so you might get an idea of how tarnished bronze might appear over time (with NO cleaning/polishing), we actually made the prototype for our "economy" model Symphony "underpart" of bronze. I've never cleaned it, but have been using it exclusively on my Miraphone 98 tuba (as I also previously used it on my M-W 5450). The shank (to the touch, and though quite dark with patina) feels smooth and not scuffed. Additionally, the thin/exposed end of the shank appears (albeit no picture) as new:

YorkNumber3 wrote: ↑Fri Mar 17, 2023 8:51 am The selling point by you and others is that stainless is wear resistant. Bronze is very much less wear resistant. The guy that spins your stuff may like the idea (easier, cheaper tooling, etc), but it would be a big step backward, imo. I’m sure someone will follow calling bs, but been there done that dealing with materials in other contexts.

Some people like to distinguish between the Jarno taper and a particular Morse taper that are used for tuba mouthpiece shanks, but - in the tuba size range - these tapers have to be taken out to four decimals to even show a small difference in their tapers... so this is not any sort of "Jarno versus Morse" issue.

Every once in awhile, someone with a receiver that is not lined up very well with these tapers (yes plural, but basically identical - as stated above) will tell me that one of our shanks isn't seating properly. I just wonder if bronze might be more forgiving and more of these receivers that drift off the norm, as such receivers apparently are legion.

Currently, we're just at the head scratching stage on this.

do you still sell the two piece mouthpiece with the brass body and a Stainless rim? How did that experiment go? might be related to this discussion

LeMark wrote: ↑Fri Mar 17, 2023 10:35 am do you still sell the two piece mouthpiece with the brass body and a Stainless rim? How did that experiment go? might be related to this discussion

Those are selling at a moderate pace.
This particular bronze alloy is considerably tougher than the yellow brass of which those are made, though.
The bronze one that I showed in the picture was only a prototype.

It makes no difference, but have you looked at the differences between the waveforms of lacquered bronze versus silver-plated bronze shanks? Could be significant…

On a more serious note, I would prefer that the dissimilar metals be the receiver and the shank, and not the cup and the shank. I want the shank to break free of the receiver much more than I worry about the cup and shank being easy to separate from one another.

One of my issues with Doug's nice pieces was that the unplated brass shank could get stuck if you left it in there for a few days and did not play the horn. (This specific horn had a Conn receiver, which is bare brass inside, to a bare brass shank.) If you twisted the mouthpiece a bit to release it either the cup became tightly wedged to the shank or the cup came unscrewed from the shank. You had to use the (conveniently provided) wrench flats to get it loose from the tuba. I have *never* had that issue with a stainless shank getting stuck like that. Your shanks always break loose easily and never cause the cup to either come loose or to be overtightened to get it out of the receiver. So easing the twist motion of the shank to the cup is NOT a selling point to my way of thinking. (Note that the ease of removal may have more to do with the surface finish of the shank than the SS.)

Unless the alloy of bronze is dissimilar enough that this won't be a factor… or is made from Oilite® bronze… <snicker>

I hope most people know (getting away from the ribbing) that striking the flat area at the bottom of the cups (outside of the female shank threads) with a hard plastic mallet or rawhide mallet is the way to free shank threads...

Also, the particular way the two components are gripped (different from what would seem to be obvious) also adds torque.

I didn’t see it—but how would this affect the price?

My students tend to like these mouthpieces, and price always comes to be a deciding factor.

russiantuba wrote: ↑Fri Mar 17, 2023 2:34 pm I didn’t see it—but how would this affect the price?

My students tend to like these mouthpieces, and price always comes to be a deciding factor.

Probably neutral, but we could have a discussion about that, I suppose.

Compared to food prices, since before the economic shutdown and the epic money printing that's been going on, we've de facto lowered our prices considerably, simply by keeping them the same, have we not?

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