rotorless F attachment. You read that right

[Burgerbob]

Here's the text accompanying this image, by Timothée Reyrolle:

Rotorless valve system!! Slik er utstyrt denne trombonen, første prototype av en idé født for noen år siden! Jeg har jo fått den overmodige lysten til å legge navnet mitt til den lange listen beskrevet de siste ukene. Historien vil si om jeg når de sveitsiske og amerikanske suksessene eller, mer sannsynlig, de mørke og glemt hjørnene av instrumentproduksjonen
Opprinnelig tanken var å bruke en bue som finnes allerede på trombona, stemmebøylen.
To påstander:
- med inaktiv ventil er boringen akkurat som ei straight trombone;
- bruk av ventilen legger kun to svake buer til.
Ikke noe mer, denne ventilen venter bare på flere nysgjerrige trombonisters meninger! Den har blitt prøvd av noen proffe og amatør trombonister, og validert som spennende!
Jeg valgte 88H-en for prototypen fordi den er den mest spilt her i Norge, men installasjonen av Rotorless-systemet er selvsagt mulig på hvilken trombone som helst. Flere 88H så vel som Bach 42B er planlagt i løpet av kommende året, og kansje en basstrombone prototype, hehe!
Kom og prøv den hos Viken Musikk, dere er hjertlig velkommen
///
Rotorless valve system !! Ainsi est équipé ce trombone, premier prototype d’une idée née il y a quelques années déjà ! J’ai donc eu l’envie présomptueuse d’ajouter mon nom à la longue liste décrite ces dernières semaines. L’histoire nous dira si j’atteins les succès suisse et américains ou, plus vraisemblablement, les recoins sombres et oubliés de la facture instrumentales
L’idée d’origine était d’utiliser une courbe déjà présente sur le trombone, la potence d’accord. Deux revendications :
- noix au repos la perce est exactement celle d’un trombone simple ;
- l’action de la noix n’ajoute que deux courbes douces.
Rien de plus, cette valve n’attend que les avis de plus de trombonistes curieux ! Elle a été essayé par déjà quelques trombonistes amateurs et pro’, et validée comme digne d’intérêt !
Le choix du 88H pour le prototype découle simplement du fait que c’est le plus joué ici en Norvège, mais l’installation du système Rotorless est bien sûr possible sur n’importe quel trombone. D’autres 88H ainsi que Bach 42B sont prévus dans l’année à venir, ainsi peut-être qu’un prototype de trombone basse, héhé !
Venez l’essayer chez Viken Musikk, vous êtes plus que bienvenus

[BGuttman]

Very interesting. I hope a short video of how it works will be available soon -- I'm having problems visualizing it from the pictures.

[Burgerbob]

Very interesting. I hope a short video of how it works will be available soon -- I'm having problems visualizing it from the pictures.

It's pretty simple, the lever just scoots the ports over. Instead of the airflow going through the main tuning slide, it goes through the F attachment first.

[Finetales]

Looks sort of like a modern interpretation of the old disc valve. Cool idea (and I always thought disc valves looked super cool), but...there's a reason disc valves didn't stick around. Of course I'd be very curious to try this, but I don't imagine things like valve trills and other fast trigger presses would be easy moving all that weight around. Happy to be wrong though.

[Tbarh]

I guess there will be some sort of "pop" when You change..

[brassmedic]

Very interesting. I hope a short video of how it works will be available soon -- I'm having problems visualizing it from the pictures.

It's pretty simple, the lever just scoots the ports over. Instead of the airflow going through the main tuning slide, it goes through the F attachment first.

Yeah, the tube coming off of the crook that inserts into the bell tail would be the fulcrum and the whole crook assembly rotates slightly around that axis. It's not clear to me what keeps the plates in contact with each other so it doesn't leak, though. Just that linkage rod?

[Burgerbob]

It's not clear to me what keeps the plates in contact with each other so it doesn't leak, though. Just that linkage rod?

Hopes and dreams.

There's also a spring connecting the two together... not sure if that's the "valve" spring or just to get that contact pressure.

[brassmedic]

It's not clear to me what keeps the plates in contact with each other so it doesn't leak, though. Just that linkage rod?

Hopes and dreams.

There's also a spring connecting the two together... not sure if that's the "valve" spring or just to get that contact pressure.

Or both? I guess you would need tension in 2 separate planes. Like a Hagmann spring. It provides both rotational tension and lateral tension to keep the valve core in contact with the back wall of the casing.

[Posaunus]

Sort of like a railroad switch?

I need more diagrams / photos to figure this one out!

[Burgerbob]

Bb side:



F side engaged:

[harrisonreed]

That's a lot of metal moving around under tension

[brassmedic]

Time will tell. Doesn't actually seem like more surface area than a Hagmann or a Thayer. I think the issue is going to be moving that much weight around and whether the plates will provide an air tight seal

[Ted]

And what's the main advantage? even less resistance?

[Tbarh]

Looks smooth!

[TheBoneRanger]

The video above simplifies it for me! Thanks!

It’s beautifully constructed, and a fun idea.

Looking forward to the independent bass!

Andrew

[ithinknot]

Fun. In addition to the seal questions... it all depends on very accurate alignment right at the end of the instrument that inevitably gets smacked into things. You wouldn't have to bump a rear bow (let alone the exposed bearing plates) too hard to put the whole thing out of service. Between that and the fact that it's TIS-only, I don't think it has legs. But it looks nicely made, and they're clearly enjoying themselves!

It puts me in mind of those tunable J-bends you see on some Minick conversions, where there's an unbraced tuning slide tube exiting the rotor, in which case you'd only have to look askance at the J-bend to crumple/crack the valve knuckle or distort the whole casing... another nice idea in principle, but too fragile for the real world.

[robcat2075]

Looks clever!

But some hipster is going to get his ponytail caught in there and that will be the end of it.

[Bonearzt]

Time will tell. Doesn't actually seem like more surface area than a Hagmann or a Thayer. I think the issue is going to be moving that much weight around and whether the plates will provide an air tight seal

The seal is my concern!!

[brassmedic]

Looks smooth!

Am I the only one for whom this link is not working?

[Bonearzt]

Looks smooth!

Am I the only one for whom this link is not working?

[JohnL]

Looks sort of like a modern interpretation of the old disc valve.

It's closer to John Shaw's swivel valve

swivel_valve.jpg

though it might be sufficiently different that it could be patented (assuming someone else didn't already patent it 100+ years ago).

[Crazy4Tbone86]

I must give credit to the clever design....I am impressed. There are a couple things that I wonder about....

1. The seal of the connecting plates. I suppose that a higher viscosity lubricant could help with the seal, but a thicker lubricant would give it a slow action. I'm pretty sure that if the plates leaked, it would be detectable in the first moment of playing.

2. The bore of the attachment section. With this type of design, the valve tubing is incorporated into the after-gooseneck section of the horn. Normally on a Conn 88H, the valve section bore is .562 inch. With this type of design, the valve tubing would probably need to be about . 593 inch. That would certainly give the instrument a completely different feel.

The maker says they have intentions to make Bach 42 and bass trombone renditions. Possibly these horns will end up being at a trombone workshop or conference in the next year or two. It will be fun to try them.

[paulyg]

I think this would be nifty to switch between two bells mounted on the same horn, but I don't see it conferring any advantages over a thayer valve.

[brassmedic]

It's interesting from the standpoint of the holy grail of trombone valve design being a trombone with a valve that blows exactly like a trombone without a valve. Thayers are pretty close, but you still have that unavoidable sharp bend in the tubing at the bottom. This one has no sharp bends whatsoever, and the Bb side is exactly the same shape as a straight Bb trombone. I think it's intriguing and I would definitely like to try one.

[Tbarh]

I live an hour by train from Oslo.. Must find a reason to go in there and try it.... Much too intriguing too not try...

[boneagain]

And what's the main advantage? even less resistance?

This is a very good question.

I try to remember that horns have acoustical impedence, which is not quite the same as resistance. One contributor to acoustical impedence is a discontinuity in the sound path.

NASA did some studies (this stuff matters when you are designing space ship ventilation) and found key relationships between duct cross section and bend radius. The only bends in a trombone (even a "closed wrap") that come close to causing such a discontinuity are in the tight 90 degree bends in a small rotor.

But changes in duct shape can also cause discontinuities, or alter the key characteristics of bell taper that mmake it possible for a trombone to even play both odd and even overtones/harmonics/insert-your-favorite-here. McCracken and others have been very careful about disrupting the taper in the neck pipe. I think the continuous taper from this point of a "tune in slide" bell is a big contributor to the sound characteristics of those horns (note: contributor, not sole determinant!)

This valve looks beautifully made. I would lay money you could run a borescope inside and NOT see ANY edges in the acoustical path. I doubt a big manufacturer could manage that. Any such edges WOULD be very disruptive.

But I REALLY wonder what acoustical effect having all that extra straight tubing so near the bell bow has. The F side is going to be a short tapered bell with a LOT of straight tubing right next to it. Kinda the opposite end of the scale from a TIS taper.

The proof of the pudding is in the eating... I'd LOVE to hear this thing.

[timothy42b]

There are a couple things that I wonder about....

1. The seal of the connecting plates. I suppose that a higher viscosity lubricant could help with the seal, but a thicker lubricant would give it a slow action.

I'm not sure how critical the seal would be if the acoustic path is clean, as boneagain pointed out. Remember the pressure is pretty low at that point, as is the air velocity, due to that 8 inch wide leak just a little farther.

If you need a seal though, it's easy enough to mill a groove in the mating surfaces and put an O-ring in there.

If you can allow longitudinal movement it's even easier.

[LIBrassCo]

I need to see this in person and give it a toot. The idea is awesome, and it appears to be executed fantastically. I have some reservations, but I wouldn't voice them without actually seeing and playing it.

[Matt K]

I'd love to see an independent bass version now!

[tbonesullivan]

Well, that's certainly interesting. I guess the main question is service life and lubrication issues. With proper oiling, standard and improved rotors last for quite a long time. with that large surface area in contact, with that kind of movement, I wonder how long it would take before the bearing surfaces wear.

[hyperbolica]

One advantage is simplicity. This design doesn't try to combine the bearing surfaces and the sealing surfaces - they are separate. Bearing surfaces don't have to seal and the sealing surfaces are flat and not taking a load. Disassembly would be worlds easier than a rotor, much less an axial. The disadvantage is all of that "sprung weight". Another disadvantage would probably be trying to use multiple valves.

[Tbarh]

He told me that a video with playing demo is coming up..

[LeTromboniste]

I'd be curious to know how the weight of the moving part (I.e. Essentially only two pieces of bent tubing and a little bit of hardware) compares to the weight of all the available rotor cores. I'm guessing it's quite a bit heavier than a small traditional rotor, but perhaps not so much heavier than some of the very large rotors with solid cores.

[stanzabone]

To me, it sort of brings to mind the old Holton Monster valve design, although they are total opposites. (Yeah, that sort of makes sense...) One with no valve, one with a giant valve. As I recall, the airflow of the Holtons is the opposite of what you might be used to.
Although I heard some that said the Holton played well, it wasn't a very popular design.

[Kbiggs]

With the exposed plates, isn’t there a chance of dirt and grease attaching to them and gumming it up, or getting into the tubes? A lot of instrument bags and cases shed.

[Timothee]

Hello everybody!

I am the maker of this Rotorless prototype. I thought well about showing it on this forum I read sometimes, wondering how much pertinent it was, then Burgerbob confirmed it by getting ahead of me, thanks!
I really wish not to be invasiv, don’t retain any comment =) I just would like to answer some of the questions, remarks. Please forgive my mistakefull english.
I translated to english the text that follows the pictures, you find it there:

Yes, Shaws disc valve is not far, but here the rotation axle is one of the port/pipe. As the movment is small (~8,5° rotation) it is not harder than other kind of lever, but its weight made the stops quite violent until I put felt in addition to the rubber stop. No « pop » noise…

The small spring connected to the brace is only to maintain the plates against each other, exactly like Hagmann (but placed differently) (I think this is the only aim on Hagmanns, the spring turns with the valve only to avoid friction). The action spring is by the lever, as usual (but very weak, the gravity does half part of the job ;-) )

About the metal under tension I think it is low: the bearing connexion stops directly on the bumbers.

The air tight was my main concern while I imagined it, and indeed the assembling of the valve must be precise. A mounting support is already designed for the next ones But, none of those who tried noticed any leak (I first, but I can name the trombone class of the Norwegian Academy of Music, two players from the Norwegian Opera https://operaen.no/om-oss/om-dnob/operaorkestret/)

Yes, fragile… I will install a kind of guard half around the plates, but anyway a shock at the wrong place can ruine a gig, more than taped waterkey and loose solder, stuck tuning slide etc. Hm, what can I say, be careful? Selvsagt it will happen at the worst moment! Invite your repairman to the gig =D

Yes I confess, I enjoyed myself a lot designing and making this! And intend to continue, it is more interesting than repairing school Yamaha cornets all day long =P And yes again, I testify that ponytail gets in the mecanic, but can be solv by the musician him/herself ;-)

A big concern, the bore in the F wrap… I choosed to keep the original bore, 14,27mm/0.562’, even if the bore at this place is 15,0mm/0.593’ after the conical gooseneck. I agree having a 0.593 would actually give a very different feeling, a wrong choice in my opinion. But not tried...
Should I make new cylindrical gooseneck and a tuning bow (not tuning any longer btw) conicity from 14,27/0.562? Could I pretend that it is still an 88H? Design a new model! … That’s another matter ^^ Anyway there is edges in our loved slide, as well as bigger leaks than any other brass! So even more important not to have some in the valve, yes, ok… ;-)

« What about the bass? » is maybe the most common question ^^ I have it in mind since the beginning of course, but I had to start with the simplest. And this valve is simple. A bass is much more challenging, especially independant. We’ll see!

A good player will make a video for me soon ;-)

[ithinknot]

Yes I confess, I enjoyed myself a lot designing and making this! And intend to continue, it is more interesting than repairing school Yamaha cornets all day long =P

Welcome!

[Posaunus]

Hello everybody!

I am the maker of this Rotorless prototype.

Timothee,

Welcome to TromboneChat.

Thanks for exposing us to your clever design, and your fabrication ability.
I love your enthusiasm and your creativity.

[Savio]

Interesting! Maybe thats the future? Seems promising! Time will show!

Leif

[LeoInFL]

I applaud the approach of thinking outside the box. This idea has potential I think.

A few questions for the designer if you don't mind:
~ while I understand the need to retain as many stock parts as possible to control costs, would a custom ferrule (almost a 'Y' pipe, but still separated) at both sides of the mated plates bring the 2 sets of tubes closer together. It seems the gap between the openings on the plates can be reduced considerably. It would result in a shorter swivel and less mass added to the horn.

~ have you considered some kind of pigtail/loop on the F-attachment to eliminate the bend? The current configuration may have issues fitting inside 99% of the trombone cases/gig bags available.

[Matt K]

Moved discussion about pronoun usage to this thread:

https://trombonechat.com/viewtopic.php?f=13&t=20768

[JohnL]

To me, it sort of brings to mind the old Holton Monster valve design, although they are total opposites. (Yeah, that sort of makes sense...) One with no valve, one with a giant valve.

From a functional standpoint, there is a valve there, it's just so darn big that one doesn't recognize it as such.

[timothy42b]

I'm curious about how the "valve" side plays in the upper register.

We've had that discussion before, and this seems like a good test.

[Timothee]

LeoInFL:
A few questions if you don't mind

The gap betweene the openings (handslide side) is 3,6mm. My thought was: bigger it is lower is the leak potential, smaller it is shorter is the movement. So i measured this distance on a Bach trompet valve (that I think we can trust ) and got about 3,5mm at its minimum. It is only 3mm on the bell side, since there is no leak risk (long pipe inserted in the bell)
The movement is not really longer than other valves, and the gain of wheight would be quite small.
About the weight, there is circa 130g difference with a regular 88H. But the horn is more forward-balanced, some players might want to add a balancer.

As the idea is to have as little curve as possible I made the F-wrap "straight" (but slightly bend to avoid the hand). Maybe a loop with the same bending radius (~60mm) would not affect that much?

JohnL

There is well a valve, yes, just the stator does not really encage the rotor. So I thought "Rotorless valve system" was not lying so much

[Burgerbob]

[Tbarh]

Bad recording, but its safe to say that the idea works!.... Have to find time to go in there and try..

[RConrad]

Really neat design. I like how mechanically simple it is, though at some point there will be issues caused by torsional stress.

[timothy42b]

That's very impressive

[noordinaryjoe]

Very clever. I do wonder about neck/face clearance and if it wouldn't be better to move the wrap to the outside of the bell section?

[Timothee]

Yes, some players have the pipes touching their neck, some others not... I will install it on the other side on the next ones.

Here a short video of a friend playing it:

I hope the link works...