Linkage Advice

[Tom]

The photos shown here are of the 4 rotors and linkage on my Alexander 163. Valves 2-4 retain their original unibal links at the stop arm and their original "T joints" on the valve paddle end. They are kept well lubricated and are smooth, quiet, and tight (no "click" or "clank" on these). Unfortunately the first valve does not retain its original linkage. When I obtained this tuba, the first valve linkage was on the verge of falling apart on the "T joint" side. I had a lot of work done on this tuba shortly after I purchased it, which included addressing the first valve linkage. Though I was under the impression that the original likage could be repaired, the tech working on the horn deemed it irreparable and installed the minibal linkage as shown.

I do not care for the minibal linkage that I have on that valve. It clicks, has a different feel, and has a longer valve stroke than valves 2-4. Unfortunately, in installing the minibal, the tech modified the valve lever, so anything done from here on will require addressing that.

I've lived with the linkage the way it is for a bit over 3 years, but am currently playing this tuba quite a bit and am growing more and more aware of and annoyed with this setup. I'm pondering my options:

I have the Dubro parts on hand to have all 4 rotors converted. I have done this on a previous tuba of mine and was happy with the results. That is one option. It would require some fabrication/modification, in much the same way outlined by Rick Denney on his website.

The other option is to convert just the first valve to Dubro and leave the others alone.

I have also considered having them all redone to be unibal links on both ends. Would be much more expensive than Dubro (which I already have on hand from another project), would probably not work any better, but would be more "elegant."

The last option is to have the first valve redone to match 2-4. This would likely mean ordering parts or having a new "T joint" made. This seems like it would be the most expensive option and would also mean going to back to what is now obsolete linkage technology.

So, knowing that I am unhappy with the setup on the first valve but that I'm perfectly happy with the OEM setup on valves 2-4, what would you do?

[Dan Schultz]

Is it an illusion... or is the paddle lever on your number 1 rotor shortened and bent forward?

If you like the old 'T-hinge' setup, you might be able to put out a call for a paddle lever that will fit your horn and go back that direction.

Aside from doing that.... the Dubro links might not be as elegant as Unibals but you'll never have a problem with them.

[Tom]

Is it an illusion... or is the paddle lever on your number 1 rotor shortened and bent forward?

Forgot to mention that. It got chopped up and bent forward.

Not an illusion, unfortunately.

[cambrook]

I trust that is your EX-techician that you're referring to?

[TUBAD83]

I would go with option #1. I checked out Rick's site and followed his directions to the letter when I converted one of my earlier tubas...VERY happy with the results (and so was the guy I had later sold the horn to). Good Luck.

JJ

[imperialbari]

Anybody knowing just a little about applied math would know that shortening the lever arm would lead to a longer throw. If you want the throw of all 4 valves similar, then you will have to make them equally long. If you shorten 2 through 4, all will get the longer throw, which hardly will be desirable. And then the bent 1st lever still might cause a sense of difference between the valves.

Will it be possible to braze an extension to the 1st lever, so that the seats for the Dubro balls will be similar on all 4 levers as measured as the distance from axle and with a similar angle to the paddle? There are too few photos for me to tell, as the evaluation shall be done from the ends of the axle.

Klaus

[Rick Denney]

Klaus is right. What's giving your first valve a different feel is that the center of rotation was raised. This is inexplicable to me--the modification that was done could easily have been done with the original geometry. It will indeed required extending the length of the paddle lever to restore the axis. If you do that, you might be able to mount the existing ball at the end of the longer lever and get the same feel as the other valves. It doesn't matter that the linkage isn't as long--that won't have as much of an effect on the geometry, even if the lever has to be shaped a bit different than the others. If restoring the throw and force is the only objective, then that's probably the shortest path to it. You could extend that lever by either replacing it or by silver-soldering on an extension made from brass bar stock.

If you want it to look more consistent, then you have to work a little harder.

The pins on the T-hinges are (on Miraphones, at least) screwed and then soldered into the paddle levers. The shell is slipped over the shaft and then the shaft is peened down to create a flange to hold it in place. It's hard to move a T-hinge from one horn to another, but you might be able to find a paddle with the T-hinge still attached. I think most technicians could deal with this pretty easily, but it will be harder than your other options if you do it yourself. If you do it yourself, the Dubro links are the easiest.

But you are still going to have to extend or replace that first paddle lever. The proper approach to a conversion is to use the same holes used by the old linkage for the ball links. Doing so maintains the geometry and that leads to the same throw and force.

Rick "suspecting that soldering an extension to restore the current paddle might be easier than finding a cheap replacement" Denney

[cambrook]

So, knowing that I am unhappy with the setup on the first valve but that I'm perfectly happy with the OEM setup on valves 2-4, what would you do?

What I would do is take it to a good tech, and they DO exist, and discuss it with them. It is not difficult to repair the original lever by brazing a replacement section on, and done carefully it will be barely noticeable.

Are the parts available from Alexander? If so you could install them yourself, so while you might pay more for the parts you will save on labor.

You have a fine tuba that you intend to keep, it's worth spending the money on getting it repaired by someone who knows what they're doing.

http://www.oberloh.com/gallery/alxcctuba.htm" target="_blank

Good luck!

[Tom]

I wasn't asking about WHY it feels different...I understand exactly why that is and Klaus and Rick are both right on in that respect. I was asking about what you would do if you had a tuba setup as I do.

I will not call out the tech on this board, but will point out that it is NOT one of the known tuba techs and is NOT someone that posts here. That said, the tech is well known in other circles and came highly recommended. It's too bad that the first valve linkage got butchered so badly since some otherwise very fine valve work was done on the horn. I have addressed this with the person that did the work and I'm not here with an axe to grind. When I expressed some disappointment, I was revealed that the "simple" linkage work was farmed out to a rather inexperienced shop assistant that thought he was doing me a favor by having installed the "expensive minibal links."

I have converted a tuba to Dubro links just as Rick Denney describes, so I know what that entails and I believe that would work well again. I ended up selling that tuba, but not because of the linkage.

I absolutely understand that anything from this point forward will require addressing the butchered first valve lever. I guess I was not clear enough about that in my original post.

I suppose the real question is should I keep valves 2-4 setup the way they are and just fix the first valve or should I just get them all changed out at once? This is really why I've lived with it the way it is so long...haven't wanted to trash perfectly functional original parts.

I would love to have this Alexander "Oberlohed" some day, but it just isn't in the cards right now. I do not own a "back up" CC tuba and have too many other things going to dedicate the necessary funds to such a project at the moment.

Also for the record, (even though nobody has asked) this was NOT Wade's Alexander.

Thanks everyone!

[cambrook]

I didn't mean to suggest that it needed to go to Dan O, I'm sure there are a few other good people who could do a great job with this issue.

If the tuba was mine I'd keep 2-4 as is and have #1 restored to match.

Cheers

[imperialbari]

You are disturbed by the 1st valve having an action not uniform with the action of the other valves.

You will not even approach a uniform action unless the 1st lever arm is restored to the same effective length as the other lever arms. The feel still will be different if the links are not the same on all 4 valves. If the mini-balls at the crank end are OK, then only put Dubro links on the lever end. That is, if you can make the push rods fit the two different types of links.

I dislike T-links very much, because they take expert maintenance to make up for wear. I don’t think they should come with new instruments any more. I have an Alexander horn with the same set-up as yours. Combining a relevant technology (mini-balls) with an outdated technology (T-links) makes the whole set-up outdated.

Klaus

[cjk]

The screws that hold the Uniball links on *may* be larger diameter and a different thread type (highly likely) than the 4-40 screws that are used to hold on Dubro linkage. I would assume the screws that hold the Unibals and Miniballs are metric, hopefully the screw holding the minibal on the first valve stop arm is the same as 2 through 4.

I do not know what size screws they are, but the holes they fit in may be too big to tap to 4-40.

I would also measure the screw that holds on the minibal onto the first valve stop arm. Hopefully the hole in the stop arm hasn't been re-tapped. I suppose somebody could probably repair that, but it's more work, and I don't know if it's difficult or easy work.

What I might do (or think about doing) if I were you is
1) Buy a $15 set of digital calipers at autozone
2) Measure the screws to figure if you need a stop arm or not
3) Contact as many repair folks as possible to see if they might have compatible parts. I would be surprised if Alexander actually makes valves. I expect they order stuff from J.Meinlschmidt GmbH. Therefore, you *might* find something that matches exactly off of a different make of tuba in a junk box somewhere.
4) contact Steve Ferguson (who orders and sells Alexanders) and see *if* he can order the first paddle, linkage, unibal, screw, and stop arm if need be.


I hope this helps,

Christian

[tubamirum]

Restore number one to the length of the other levers.

[Lee Stofer]

Here's my $0.02;

Since you are happy with the action of valves 2,3, and 4, I think that restoration of lever and linkage #1 would be your best bet. And, it should not be very expensive, either.

I strongly disagree with anyone who thinks that the "T" universal-joint-type linkage mounted to the valve lever is obsolete. Properly set-up and maintained, they work as well as anything else. You do have to know what you're doing, to correctly repair or maintain them.

You may think about an instrument that you play, or have played, where the universal joint-type linkage is loose and rattly, a real annoyance. What is to be done about that? The hinge tubes can be swedged with swedging pliers, just like woodwind keys are in any decent woodwind overhaul.
The carefully-applied pressure of the swedging pliers will both eliminate the play between the hinge tube on the outside and the hinge rod running through it, and slightly lengthen the hinge rod, eliminating play in both planes. These linkages almost never wear out (as ball joints can), but need periodic maintenance. If well-oiled, an adjustment every 5 years or so should keep them working well for at least 40-50 years. I like to use Hetman #15 Ball Joint lubricant on these linkages, as it protects them and helps them keep really quiet.

If you find a competent repairman with silver solder, nickel-silver bar stock, the right tools and a bit of patience, he can re-build the lower 1st valve lever and your linkage, greatly enhancing the performance of your instrument and it's value, too. This sort of situation is the main reason why I suggest that instrument repair students that are considering only studying brass instrument repair also study woodwind repair. Key-fitting, key-swedging, and key-rebuilding are very, very handy skills for brass repairmen, too!

Note for Repair Techs; if you do not have swedging pliers with the right-size holes for swedging the larger linkages, such as Alexander, Rudolf Meinl or Hirsbrunner tubas have, take an old set of pliers and re-size the holes to tuba- and euphonium sizes, and keep that pair just for brass instrument work. That is how I recycled some old Ferree's swedging pliers.