Kurath/Willson F Tuba — Adding a 6th Valve

[the elephant]

This thread applied to all Kurath F tubas as well as their direct follow-on, the original Willson 3200-FA5 up to when that was replaced by the 3200 XS and XL. The XL is very similar, so these might apply to it as well, but I wouldn't modify such a spendy tuba as these are still pretty new. The original FA-5 is an old horn now, and the Kurath is its daddy.

My last thread about this tuba lasted for two years! I had finished the specific topic some time back and had gradually shifted over to other stuff. I'm going to redraft all that "other stuff" here and take out all the conversations and my tangents and dead-end ideas.

Thank you very much for reading.

Wade

[the elephant]

Okay, first off: I added a 6th valve. I have no idea why I chose to do this except that I had this thin apart all the time and I had the stuff needed to do this at hand. Or so I thought…

Also, I've played a number of six-valved F tubas (all rotary) that did not impress me at all. All of them were so out of tune that my opinion came to be that if a horn had a 6th valve it was a way for the maker to try and excuse terrible acoustical research during the development of the model. In other words, a six-valved tuba was inferior and *needed* all those extra alternates to be played very well in tune in an ensemble.

Yeah, well, MAYBE this is the case for a few F tubas, but by no means all of them. I just did not know any better back then.

Along comes the WWW and in 1996 the original version of this community came along at Sean's original BBS. And this guy up in Memphis started in on F tubas with 6 valves. Joe's ideas about how the 5th and 6th are tuned and are to be used were completely new ideas to me. I was taught that a 5th valve was cut to be halfway between 1 and 12, so a 1.25 whole-step loop. This allows the player to get the low note that needs to be played 14 in tune without a slide pull. On a CC tuba, this would be low F. At that time, 5th was still frequently a flat M3, so low F would be a very solid 235. I still really prefer that low F to a low F played 45, which has never felt very good to me.

So I was taught that the 5th was a 23 combo that was overly long to allow 235 to work. The only way to get this pitch on a 4-banger CC tuba was 14 with a long pull or 124 with a long push, so the flat M3 valve was a real gem if you had the extra money to order one. (Back then, 5th valves frequently were an optional upgrade.) So that made sense to me and thinking of 5th as a certain valve combo plus enough to make it play in tune without a slide move carried over to my first tuba with a flat whole step 5th valve.

So I thought a flat whole-step valve was just a 1st valve with a built-in pull. and @bloke slowly started to creep into the white noise that dominates my mind, sometimes. Over many years of hearing him preach that his 6-valved F tuba was sort of like a double tuba (yes, you did make that comparison a long time ago, which was why I started to listen to you) in that it was a three-valved tuba with a sort of " trombone F attachment" called the FOURTH VALVE that sort of placed the tuba into CC, and the 5th and 6th valves were cut to be used as the 1st and 2nd of a CC tuba. My takeaway from this was that my F tuba could be like this, too, since it already had a CC 1st valve. I confirmed this with a tape measure; it is indeed the same as a 1st valve loop for a CC tuba. I did some thinking and realized how much easier it would be to play this tuba from low B natural down to open low F. Then I realized that Joe was *also* spot on regarding all 6 valves giving you an in-tune low F with the same sound and response as the low G and Gb. Then I thought about all the time I had wasted for years working on making the loud low F move up the scale through Gb or G without the horn backing up and those notes not wanting to speak as freely as the open note (which was frequently sharp, anyway). I could play the runs in the first movement of the RVW with a valved low F and have it be better sounding in minutes of work, with the same, predictable response as all the other notes in the run.

Mind.

Blown.



So I decided that while this tuba was all torn up I would install a 6th valve.

I had no idea just how deep this can of worms would be when I cut the top open.

[the elephant]

When I tried to use an extra (brand new) 186 valve left over from my two 186 restorations, I discovered that one of my pet peeves (cork plate and stop arm "clocking" on the face of the rotor case) would have to be worked around. It was not a bad thing, just time-consuming, and in the end, it frequently looked like a mod rather than the factory look I was hoping to get.

I also needed to up the bore to help with the taper re-do I was working out during the re-tube project. There was a natural space for another rotary valve on the tuba, but there was a small taper in that 2.5 inches of space. And, lastly, if this was going to work I needed to locate a place for the new slide loop to live.

Together this combined into requirements that made me decide to have Miraphone make me a bespoke valve with custom knuckle bores and directions as well as the layout of the stop arm and cork plate…

… and that led to me realizing that I needed the 6th to come before the 5th, with the 6th being the smaller valve. The Kurath rotor was sort of leaky, too.

So I bought TWO bespoke rotary valve units from Miraphone. And they are WONDERFUL! I love them.

And my 5th lever being for the right thumb? Yeah, I wanted to retain that functionality. Call it training wheels, if you like.

And two-handed tubas did not allow for facile movement of the 1st slide, which is where my hand has been trained to live since the 9th grade.

HS Band Director and Fourteen-Year-Old Wade

BD: Mr. Rackley, do you not hear how sharp that note is?
Me: Sure I hear it.
BD: Then would you PLEASE fix it???
Me: How?
BD: Remember how you did that on your trumpet?
Me: Yeah.
BD: THEN DO THAT. DO IT EVERY TIME AND NOT WHEN YOU FEEL LIKE IT. REMEMBER IT EVERY TIME.
Me: Converted "Slide-Puller for Life"…

I congenitally cannot have my left hand anywhere but on the 1st slide, or wherever it is needed for a given note. It is hard-wired into my brain. Old Mr. Vanderhider made sure of that.

So HOW WILL I RIG THIS EXTRA VALVE UP?

[the elephant]

Following Joe's ideas about how the 5th and 6th can be used as the 1st and 2nd of the horn with the 4th valve down (amongst other uses) I very much wanted the two valve levers to be set up as a 1st/2nd system. This idea made a 6th valve much more usable by my feeble brain. I could do this.

The Rudi 6-banger one of my students had did not use this system. The 6th was a flat whole step, but the 5th was a SHORT HALF STEP. Obviously, this tuba was probably custom ordered, so this was why I did not understand how to use it. In fact, it was a doggy out-of-tune beast and the 6th was added later specifically to correct this tuba's flaws. Neither the owner nor I could really figure it out. He did a great job on the RVW, though, with it sounding very nicely in tune, but he used that 5th valve in a lot of weird places, and 6th was his 5th.

The setup was left-hand 5th with a left-hand 6th added on top of that, so the 6th index finger and 5th middle finger. Or sharp half-step left index finger and flat whole step left middle finger.

This did nothing to make me want a 6th valve on anything and reinforced my idea that a 6th valve was added to correct some of the flat 2nd valve pitches in the staff by using a shorter slide. This folded in nicely with the number of 2nd slide kicker levers being installed on horns at that time: 6th valve was an add-on to fix desperately out-of-tune notes on the 2nd slide overtime series.

See why I was so skeptical of six-valved tubas at that time?

[the elephant]

Once I had slowed down enough to listen to what Joe had said about his Symphonie over and again (and I had a very good F tuba to fart around with) I decided to add that to my horn.

The original (probably Jürgen Voigt) rotor was replaced as it was leaky at the bearings. It was also too small in the taper, so I decided to bump it up just a bit. The pistons were 18/18/18/19mm, but the entry into 1st was actually 17.5mm and the exit was 18mm, so I made 1st 17.95 mm, which was Miraphone's nearest stock tube size. I used this stuff to make 2nd slide, too.

The 3rd loop went from 18mm to 18.73, again, because this was the next size up in Miraphone's measurement system. I can easily get Miraphone tubing. I cannot easily get mm/half-mm nickel silver tubing, so I went with this imperfect solution. I altered the piston knuckle ends to fit the tubing. The passage through the pistons is about an inch, is bent to one side or the other in a curve, and has small "blisters" due to the valve stroke. They play VERY well, and with all the disruptions in the shape of the tube and the reductions in bore due to the blisters, I figured (correctly, as it turned out) that making alterations to the bore of the much longer slide circuits was not affected at all by the slightly pinched nature of the existing ports. So WHY NOT DO THIS???

The 4th valve was natively 19mm and I bumped it to 19.54mm so I could use the native 186 tubing and crooks.

So 1st and 2nd valves are essentially the same size, the 3rd is just under three-quarters of a millimeter larger, and the 4th is about half of a millimeter larger. The taper rate is a little more in-line with the leadpipe and the bugle. The 5th was too small, and then the MTS crook explodes upwards in bore size. I can only imagine that when he was preparing this to send to Dan P. as an evaluation instrument that he was unable to locate a larger rotary valve on time so he installed this one, and then made a ridiculous slide crook to get the bore up to where he wanted it to be. The rotor that came on the horn was 20mm. 1, 2, and 3 were a straight bore, then 4 went up a full mm, then five went up another full mm, but it took three inches to get there. then the small side of the MTS blew up from 20mm to 24mm in just a few inches. Then the large side of the MTS had an internal step of about 2mm all of a sudden.

Again, it seems like he had planned on a 22mm rotor, which would have smoothed out the taper to match the rest of the tuba, more or less.

It has been pointed out to me that at the last minute, he may have decided that the dogleg and the 4th valve tapered up too fast and he swapped in all the smaller stuff and then joined the two ends with the big step in the MTS end and the wild taper on the crook of the slide. A last-second adjustment to make the sale, perhaps? This would have helped the horns tone and response in the staff and above. But then the low Bb ended up with this pinched quality of sound.

I have measured a few later Willson 3200 tubas, and the exit from 4th and the entry into the dogleg are the same as mine, so I tend to think that what I have was what he wanted and that he changed it to be more like what I now have. Or he added that ROTAX valve thing and altered all the problems, blurring the solution. In truth, the tuba, quirks and all, plays quite well, so perhaps he never put *any* thought into this. But boy, some of his decisions make no sense to me, if that is the case.

Whatever.

So my Miraphone replacement 5th rotor ended up bumping from 20mm to 20.35mm. I used all matching slide tubing and crooks for this, too, so the fit is very nice. I then bumped the exit port up one notch to 21mm and opened up the MTS crook at the small end just a bit. In doing this I discovered that the MTS crook shrank in the bore from 20 to 18mm, which is just flat-out stupid. No wonder that part was so weird. So it moves from 20 to 18 to 24? Lots of beer must have been consumed when that crook was being bent and balled out. Wow. This is a premium instrument.

I corrected the crook to have a very nice, even, and ROUND taper. After reassembly, the tuba plays much more evenly.

At the other end, I made a smaller leadpipe. It is only about 13.5mm at the small end. It was 15.5mm and had very little taper. It was also very poorly installed. The angle needed to place the mouthpiece where it ended up was not accounted for by bending the pipe. Again, the pistons were purchased, and the later Willson horns used a different set. I think he designed what he wanted, then kludged this together to get an excellent prototype of the design into the hands of the importers. So there was this massive gap between the end of the leadpipe and the 1st knuckle. Inexcuseable! But, if this was a prototype horn and it played okay, I can see this getting out the door.

When I decided to add a 6th valve this is when everything got weird on me.

[bloke]

I'm thinking the OLD M-W 46 model featured 5 and 6 in the opposite order (compared to the semitones in the right hand) simply because it was easier to puzzle-piece the instrument together in that manner.

OK...yep...' found a picture of one:


If my F tuba demanded that I "work" the #1 slide (I have no idea why it doesn't?), I'm not sure what I would do.
It's not particularly accessible (that crept-into-English-language-in-1997-word again...) "ergonomically".
I enjoy using my right thumb to push 5 way-WAY out for a 561234 "gritty"/in-tune/easy-to-control 2nd-partial "low F" (as well as barely kicking it out for a better-than-234-and-fine-tuned-564...That would be A-natural).

...but I have another available thumb, so I guess I could have hooked the right thumb up to a #1 slide trigger, were it that I needed to do that...and Roger Bobo's left-hand thumb system (then) would have been the one used push out the #5 slide.

Most all of my tubas feature stuff-that-ain't-relatively-the-same as the others, but that stuff sorta helps me remember which instrument I'm playing.

"Low G" is written into a bunch of tuba sheet music, and 5-2-3-4 is stinky-sharp (with slides in most folks' default positions) on most any modern-day 5-valve tuba. It's pretty luxurious to be able to mash 5634 and just have it be "on the nose". 6 can also (possibly...and it depends on "which way wonky") be a lifesaver with some tubas with a very wonky/inconsistent 2-3 overtone series.

I've shat all over your brand-new formerly-clean thread enough for now...
Feel free to ask that this comment be deleted by them folks, and we're still friends.

...and it's HARD to stuff TWO rotors into 4-piston instruments...I'm stalling - right now - building my bass trombone cimbasso's valveset, due to this TRVTH.

[the elephant]

Pics of what I have been describing…


Between the dogleg and the end of the MTS, there are FOUR layers of tubing, with an internal step into the dogleg of just over two millimeters. On the small end, if you look carefully, the inside slide tube is about 2 mm larger than where the crook comes out of the ferrule. It matches at the ferrule and suddenly necks down to 18 and then expands up SIX FREAKING MILLIMETERS to the large side, which ends inside the dogleg at 26 millimeters!


Here is the corrected MTS. (I am neither skilled nor educated enough in this field to be able to correct someone like Herr Kurath. I am correcting what I believe to be compromises that he had to make for whatever reason. This tuba plays well, but it was a kludge, plain and simple. His production model Kurath and Willson tubas were not like this at all, to the best of my knowledge, having had the bugs worked out as a part of the prototyping process. I just got "lucky" to buy this tuba with its various "sort-of-like-this" solutions rather than a nicer production horn. Note the small end is larger, the taper of the small half of the crook now matches the rest of the taper somewhat better, and the large end is not larger because I removed the two extra layers of metal and simply made stuff fit correctly. I had to trust that his measurements were good at both ends and then try to smooth stuff out in a way that makes more sense to me. I have been very pleased with the results. Math is fun. Nope.


Here is how the leadpipe was installed. No bueno, señor. No bueno.

[the elephant]

So all that voodoo was done, and the big space between the 4th and 5th remained, with this funny, little tapered piece between them. I realized that there was just about enough room for another valve between the two. I did not want to have to redo the entire 5th circuit, and 6th is pretty short. So I decided to insert the new 6th between the 5th and 4th valves.

Weird. I know.

So I ordered that previously mentioned additional bespoke valve from Miraphone. It is the 19.54mm valve used on the 186, with an exit port the size of the larger 5th valve and one knuckle turned in a different direction. The cork plate is mounted 90º from where it normally is. It works really well and allows me to stuff the little slide loop into a place that is both out of the way of everything and easy to access the slide. Nice!

In fact, I altered my 5th valve to fit the larger exit tubing to help the small side of the MTS, and the cork plate is oriented wrong, so I had to do some surgery to the stop arm to get it to work. I liked the custom valve so much that I decided to order one for 5th at some point so that all that custom hacking would be factory work and attractive.

Now we are sort of up to date on the 6th valve situation.

[the elephant]

So now that I have learned a few things about my re-tapered, re-tubed Kurath, I want to do all this again, but correctly. I had to learn a lot first, and now I am ready to start over.

Unfortunately, I have decided that the two rotor casings need to be made again.

I have decided that my difficulty with the 6th lever is that the valve stem needs to be on the other side, next to the stem of the 5th. However, the SLIDE needs to either stay put or to also be flipped so that it is on the other side but pointing in the opposite direction. Right now it points up, but if I flip it the slide has no place to live. If I flip it and then point the slide loop DOWNWARDS all sins will be forgiven.

Well, that is a lot of money to just drop like that. And after all this mess I need to very carefully annotate my photos or diagrams to Miraphone so that they come to me *exactly* as I need them to be. I have had two custom parts come to me that did not work because what I wrote could be misunderstood to mean something else. I am learning how to communicate with Eva and the gang in Waldkraiburg using very clear photos with very specific annotations. It is a royal PITA to try and return a custom-made part when they are at fault, and you CAN'T return a custom-made part if it is YOUR OWN FAULT. If it was due to your own mistake, to even try to return it seems pretty scummy to me. So everything must be very specific and exact so that there is zero room for interpretation.

Example: I ordered a larger leadpipe for my 186 because the way I play the horn allows this to work very well for me in the orchestra. I ordered a 188 leadpipe bent to fit a 186. The 188 leadpipe is LONGER than the 186 leadpipe, so the technician managed to fit the longer leadpipe into the frame of a 186. This was a major PITA for the tech because it was nickel silver, a material much hated for its being difficult to bend cleanly. To avoid this in the future I will state something like "Please bend in nickel silver the pipe used on the 188 so that it fits the 186 frame, but shorten it to match the 186 pipe in length and form."

Live and learn.

[the elephant]

I'm thinking the OLD M-W 46 model featured 5 and 6 in the opposite order (compared to the semitones in the right hand) simply because it was easier to puzzle-piece the instrument together in that manner.

I thought that this may be the case. I have even read that some Chinese-made Fs with 6 valves have to be ordered with 5th and 6th on the 1st and 2nd fingers, otherwise, they come from the factory with 6th on top of 5th.

stuff about the word "ergonomically"…

That word has been in use for most of my life. I learned it in middle school. Here is something from the web about the origin of the word:

The term ergonomics originally comes from the Greek words ergon (work or labor) and nomos (natural laws). The fact that the word ergonomics was coined by a Polish scholar, Wojciech Jastrzębowski, in 1857 became widely known when his book in Polish was reprinted in an English translation in 1997.

However, the Pentagon has used it since WWII for design specifications of armored vehicles and aircraft design competitions. My daddy was a grunt in the Marines and he knew it, too. He used it when drinking beer and slamming the ergonomics of the controls of the backhoe and road grader he owned as a part of his construction business. So he learned it somewhere, too. I first heard it in common use in old Honda TV commercials in the early 1980s. But it did not catch on until 1997 for some reason.

"Low G"… 5-2-3-4 is stinky-sharp…

We tune our horns completely differently from one another. This same partial using this same fingering on every horn I have ever owned has been very flat, but not flat enough to use 534 in its place. I tune with 4th out to be in tune in combination with 2, and I used 13 instead of 4 for just about everything. Remember, I started as a slide-moving trumpeter, using 3rd more than 1, and using 4th as a pre-tuned alternative for 13. All my tubas are three-valved with 4th being this extra thing that makes tuning easier, and 5th is this nice add-on.

With the 6th added I finally feel I can use 4th as a type of "CC attachment, so I am now tuning my 4th much further in because 6th gives me the 24 note IN TUNE. Nice.

Feel free to ask that this comment be deleted by them folks…

Why would I do that? You are one of the only people who read my drivel. Keep posting.

… it's HARD to stuff TWO rotors into 4-piston instruments…

Man, you are not kidding. If you can shoehorn the valve into a good location, you have to find space for the slide. In the case of this tuba, the valve is oriented 180º out from where it needs to be if I actually want to someday connect the lever and the valve stem.

OMG, what have I done to myself with this project? My ongoing loss of IQ points is palpable…

Heh, heh, heh…

[the elephant]

So I have the valves and slides on. The 5th lever/linkage system was one of the trickiest bits of kit I have ever made. I made ten versions, each trying (and failing) to locate exactly where this long "drop rod" from the lever at the front of the tuba would be mounted back to where the lever for the upper 5th valve lever would live, almost all the way through the guts of the valve section. I had a vague idea of how this would work and where it all would go, but I could not fashion the long, angular lever in a manner that did not flex terribly when the valve was used. The lever had a huge amount of slop because it would hit the bumper on the cork plate and then keep moving about half an inch! Again: No bueno, Señor!

I talked to @Rick Denney about this, trying to figure out whether I needed to use flat bar stock and all this other stuff. Rick essentially said, "That design with that material is probably going to flex no matter what you do."

He was correct, as always. So I looked into different materials and bar profiles and sizes. What I finally ended up with was based on some help from a nice lady at McMaster-Carr. (I have kept in touch with her and she helps me stop wasting time and money. She is probably not supposed to do this, so I will not share her contact info. I think she is an engineer who works for them and who may have been stuck with answering their technical assistance line one weekend. She gave me her name and her private office number because her son played drums in his school band and now is an instrument repairman. She thought my issue was interesting. So I have a contact "on the inside".

She suggested their 7/32" 303 stainless steel rod, warning me about the work-hardening it would demonstrate pretty much as soon as you bend or drilled it. She gave me some practical tips for doing what I need to do. [I called her back recently to tell her of my difficulties with this stupid 6th rod. She looked at my photos and gave me some additional ideas, et voila! it worked and I have the rod bent.]

The 303 rod is a PITA to bend by hand, but when it is done it is far more rigid than nickel silver which is anything smaller than 3/8" OD. This stuff is great!

[the elephant]

So I eventually changed how I wanted to tie in the upper lever to the lower one, and that horrible "drop rod" was deleted. My weirdly bent lever can now be remade (sigh, again) without the weirdly bent part. It can look normal and be easy to make. The new tie-in location removes the thumb lever itself from the system. Now there is a hinge directly on the lever to the rod that goes to the valve. The lever is more than 3" higher than (forward of, actually) the valve stem, so I made a VERY rigid Z-shaped rod to connect the lever to the valve.

A long rod shaped like a Z cannot be connected using the Minibal links we all love (to hate). the corners of the Z would flop around and create a lot of silly noise and perhaps some minor damage to the valve casings. I made a very rigid, single-plane hinge between the rod and the lever, so there is no rotation possible except for the small amount of deflection needed for the rog to rotate around the stem. The valve end uses a larger Unibal (Swiss-made, and very trick) that came on the tuba.

After playing this tuba for some time with the re-tubed machine, I find that I only very rarely have to move my 1st slide. So the reason to keep my hand pinned down in that spot is gone.

THIS OPENS UP A LOT OF POSSIBILITIES.

I have also decided that I probably don't really need the 5th to be operable via both the right thumb and the left index finger. Once I get the 6th down in conjunction with the 5th on the same hand, it just won't be much of an issue, I believe.

THIS OPENS UP EVEN MORE POSSIBILITIES.

[bloke]

My 4th slides are usually set... (typical 5-valve system)
- good for the second partial 4th valve pitch
- if really lucky, good also for the 4th valve 3rd partial pitch (but often: 1-3 for this one, instead, with 4 as a flat-tending alternate)
- also if really lucky, regular-ol' 2-4 is only a "trace" sharp for the 3rd partial pitch (as - acoustically - 3rd partials tend to drift low)
- whereby the 2nd partial pitch (mostly likely) must be played 5-2-3
and...
- 5-4 works without moving anything
- good ol' 2-3-4 does what it does
- 5-1-2-4 works for the next pitch (particularly if there's a hand on slide #1)
- 5-2-3-4 is (again) "stinky" sharp and something asks for a frantic pull (or a false tone, or whatever)
- mashing down all the buttons is just about right for the semitone above the fundamental

================================================

I'd LIKE to be able to brag that my F tuba 5-6/1-2-3-4 fingers are "automatic", but - just as an example - throw that quintet arrangement of the West Side Story Overture at me (with the F tuba) and - well... - not so much.

That having been said, it's much more automatic than 5-valves-plus-a-second-slide trigger (which is my cimbasso set-up). When I encounter low-tuba-range (often rock, R&B, or jazz band) licks in the really low range with only 5 valves and a 2nd trigger, (yup) I gots-tah practice (and maybe WRITE IN THE FRIGGIN' VALVE COMBINATIONS !!! ), as I have NEVER owned a 5-valve F tuba.

...A second slide trigger is nearly as good as a sixth valve...so you don't have any "ergonomic" way to rig one of those up, correct?

I'm thinking that - when a widely-read European book was translated to English (in the late 90's) that word appeared in print in its English form.
Suddenly, it was everywhere (around the same time "gravitas" appeared in the Bush-haters' vernacular). That having been said, it's pretty easy to hate the Bush family.

Prior to my oldest daughter's first birthday, she had never heard the word "gloves" (born in June...put gloves on her for the first time in February...extremely early talker)...so she came up with "hand-socks".

[the elephant]

Re. 4th tuning: What I was trying to say (poorly) was that I never, ever use 4th alone except as an alternate in fast scalar stuff. So I have always had it set very far out so there were no sharp pitches when using it. This makes my low A (234) very flat, my G 2345) VERY flat, and low Ab (1245) flat, but fixable with a push on 1st. Low Gb 1345 is pretty decent. Glw Gb 12345 is good if I have to play that note really loud.

[the elephant]

Re. "ergonomic" - no it was used in the military, as I said, since WWII, and it was in my textbooks in middle school in the late 1970s. Again, it was used a lot in old Honda commercials in the early 1980s. You must have been reading the paper and drinking coffee during that time and missed it. I have used that word regularly since high school. (Probably because of Honda.)

[bloke]

When I owned a Gronitz PCK (back when Gronitz made 'em) I eventually decided that I didn't like the response with much of anything played with the 4th valve...and only used it when I absolutely had to (period).

Man... I was really workin' that #1 slide.

Guess what? I ain't got it no mo'.

Still...it' was good and sounded nice on recordings.

open G up in the staff: flat (weird)

That thing that Matt built a few of and sold out of Dillon: really similar, but weighed more

bloke "How's THAT for friggin' off-topic crap?"

What we need are for these upcoming gigs to already be here and/or for temps to be back in the 50's - so we feel like getting out and working on (whatever)...horns/cars/firewood-cuttin/fence-fixin''...ANYTHING but this b.s.

[the elephant]

So if I no longer need the right thumb lever, and I no longer need the 1st slide (both essentially acting as "training wheels" for a guy trained to play a 5-valved tuba and ride the 1st slide as needed) I have essentially a clean slate for the linkage rods because I can now freely change around how the two rotors are oriented and all that fun stuff.

I like where my levers are, but I no longer *need* them to be there. So now I will design a system that makes more sense and is easier to make.

This summer I will lay out and order two new valves and then connect them to my levers in the easiest, most direct way.

Until then, I plan on using the 6th link arm I made recently to get me through this very busy season. I may leave the 5th as a right thumb setup for now just to get this horn fully playable ASAP.

The 6th linkage rod I would love dearly to simplify by using a different 6th valve…


Here are a couple of early attempts at the 5th valve Z linkage rod…


This is the current lever with the beautiful little two-plane "T" hinge that connects to the Z rod. Note the drop bar with the doohickey on it. That is now gone and the lack of a need for it will allow me to finally make a "simple" (normal) lever… if I even retain a right thumb lever at all…


Here is the final 5th system with the Z rod…


You can see the new lever rack between the 1st slide and bell. I love this tuba. It's going to be a great 6-valved F tuba. Some day. Heh, heh…

[Rick Denney]

Still catching up on the thread, Wade, but I agree with your secret McMaster source--303 (like most steel) has 65% more material stiffness than nickel-silver. So, for the same diameter, it will show 65% less strain (deflection) under the same stress.

I think the only way to get stiffer with metal would be to use carbide. Of course, you might as well make it out of glass, which is actually less brittle than carbide.

Rick "strength is a whole other thing" Denney

[jonesbrass]

As someone who owns an old 3200-FA5 and is a fan of good six-valve F’s . . . I’m enjoying this thread!

[bloke]

Still catching up on the thread, Wade, but I agree with your secret McMaster source--303 (like most steel) has 65% more material stiffness than nickel-silver. So, for the same diameter, it will show 65% less strain (deflection) under the same stress.

I think the only way to get stiffer with metal would be to use carbide. Of course, you might as well make it out of glass, which is actually less brittle than carbide.

Rick "strength is a whole other thing" Denney

This is really off topic, and - as this will derail for a couple of posts, I hope it gets right back on track...
I put two floor pegs on my cimbasso to avoid rotation, but - even though they are of a fairly stiff alloy of stainless steel according to specs compared to others, they still flex. I guess I'm going to have to go to something larger in diameter other than stainless steel, because (current are 8mm) something like 3/8 in diameter stainless steel would start getting really ridiculous, but I'm going need to find something that's within a diameter that's manageable yet not flexible. I'm guessing I'm going to need to go to something larger that is hollow with a fairly thick wall.