announcement: There will be NO YBB-321 (Bach stencil) repair thread.

[bloke]

The only currently remaining school repair in the barn - at this time - for me is one of these wretched things - per typical: squashed flat and full of lime scale. I will not document this repair. I'm going to try to fast forward through it (Sun-Mon) so quickly that (hopefully?) even I myself might not even be aware that I'm executing it.

bloke "Man, I hate working on these damn things."

EDIT: Mrs bloke just saw me posting this, and advised me to be careful to not get my head stuck in the bell... correction: I misunderstood. She does want me to get my head stuck in the bell.

[bloke]

I lied.

The (horrible condition) bottom bow is off, the lower inside bow (beat up) is off, at least two braces are busted (probably more) and a whole bunch of those detachable brace screws (I believe I have some in stock) are missing. Of course, the bell looks terrible, the upper bow is flattened (where it inserts into the bottom bow) is currently only an inch wide, and - to add injury to insult - this dogleg (which extends UNDERNEATH the #4 casing) was smushed EXACTLY in the shape of the #4 piston...
...I KNOW what they did, because they handed it to me with all four pistons removed:
scenario" They couldn't get the 4th piston out of the casing (due to a big ring of lime at the top of the casing) so someone had the brilliant idea to remove the plastic valve guide, and pound the piston out through the BOTTOM of the casing (not bothering to notice that this dogleg was in the way)...
...so this dogleg had a epic flattened area in it that was shaped precisely like a Yamaha tuba piston: an epic dent which consisted of a convex cylindrical area with a nice flat bottom to it.
Here it is after annealing it, screwing around with it, and silver-brazing the cracks they caused via the extra-sharp-edged piston-shaped dent.

OK: (admittedly) I've never seen this particular dumbass thing done to one of these before.

bloke "We live on to the next day to experience new things, do we not?

[York-aholic]

At least they gave you something new to look at and think about...

I suspect that you will never truly be able to say, "Now I've seen it all." because the next genius will think up some new genius way to mangle up a tuba .

[bloke]

[bloke]

There are no Yamaha 201/321 bottom bow "molds" for repair shops to buy and (well...) they wouldn't work anyway.

When the side of a bottom bow is crushed nearly 100% flat, there's little more to do - preliminarily - than the pry on it with screwdrivers, beat tapered pieces of not-particular-large-diameter wood through it, and whack on it with (yes) a 3-lb. sledge and beat down on it with something not too different from a framing hammer.

This is to the "let me see - ?? - if I can begin to use brass instrument repair tools on this thing" stage:








Also, if band directors don't want us to drag their feet getting their stuff fixed (or charge four-fig. prices to fix single instruments), they shouldn't allow their stuff to get to the point that it SUCKS this damn bad...and yes - I'm aware - corporal punishment is no longer allowed...

[bloke]

Just as I suspected - and I just inspected it today - that fourth piston being driven down to the bottom and articulating that dogleg so severely ended up ovaling the threads at the bottom of the fourth casing. Boy was it fun fixing those. Of course, the threads were ovaled towards the most difficult side to repair -"which was in between the 3rd and 4th casings. I had to use crap like a skinny metal bar and flat bladed screwdrivers to beat those threads back into a round shape with a dent hammer, push back the other way by beating a approximately correct size barrel-shaped dent ball down through the bottom of the casing for about 3/16 of an inch, and then running one of those brass valve casing laps in there the same distance. It also required putting the bottom valve cap on (getting it to turn a very small portion of a turn at a time) tap tap tap around the sides which were not very accessible at all, and so on and so forth. The bottom valve cap now screws on and - although I am currently dissolving all of the lime out of the casings - pistons do seem to go up and down in that casing and we will see if the casing is actually okay, once all of that lime is dissolved away.

I hate hate hate hate repairing these pieces of crap, and I hate hate hate hate what young scholars manage to do to them.

[bloke]

For the last day or two I've sort of been doing "anything but this damn thing" to fill the days up, but today I went out there today and - maybe - it's nearly ready to stick back together. I unfolded the mouthpipe tube today (next to the receiver) and silver soldered the cracks back together. I also got a lot of work done on the two upper bows of the instrument, which I left braced together.

There are some smaller dents in all of those knuckles going into the valve casings of course, and I'll see about how easily those might mostly be removed tomorrow.

[bloke]

BELL:

Make the small end into a perfect circle, the rim rocks on the floor.
Make the rim into a perfect plane that doesn't rock on the floor, the bottom end is oval.

backandforthandbackandforthandbackandforthandbackandforth...

...so I will straighten the rim once the tuba is all put together.

[bloke]

Due to the fact that Yamaha valve casings are very thin-walled and there's no room for relief areas at the tops and bottoms where the male threads are, as the bottoms of casings #'s 3 and 4 were screwed up by Young Scholars, I'm having to do the typical fight of either getting the valve to go to the bottom of the casing without sticking or having the threads work, so I gave up and bought a rethreader for the bottom threads. I'll get the casings round on the inside, and then I'll recut the threads on the outside, so this one's sitting until the tool shows up.

What is amazing is that this was actually the last repair job that I had sitting around here, so I'm actually moving on to restoring some instruments that some people have been waiting to buy from me, if I can ever get them in nice condition. That's a real change, but I'm getting ready to get hit with repairs again. I just haven't picked them up from the people who've called me.

[bloke]

OK...

All of the valves work and feel like new valves, all of the valve casing caps screw on and off - and feel like new caps. (' wasn't sure I'd get to this point, with this particular pile of junk...)

Slides #'s 1,2, and 3 slide in and out nicely.

#4's fit is marginal. I'll be monkeying with that one.

I won't reinstall the main slide dogleg until I'm satisfied with #4.

Once the last two of the above punch list are addressed, the bottom bow (and replacement used cap), bell, and mouthpipe will be remounted.

There are still hours of work left to do.

I dislike working on these very much, thank-you, and - once put back as they originally were - there (no offense to anyone, but...) isn't very much to show for it.

I'm told I resent science. I use a good bit of arithmetic, a bit higher mathematics, geometry, general science, and physics to get something like this back as it originally was...but that discounts "touch", and "avoiding detours" aka "doing dumb stuff" (as - without avoiding detours - I would never get hopeless crap such as this back as it originally was). Also - when boiling everything down to science, the emotional aspects of working on instruments such as this (as an example: hate) are ignored.


bloke "I wouldn't buy this for what I'm charging to fix it, because I would feel guilty selling it for that much or more - and it ain't all that much money."

[bloke]

OK (other than polishing away burned lacquer and solder mess tonight after I get home from a rehearsal), this is as much as I'm going to do.

It's all good and plays (as these play).

...what a MESS it was...

[York-aholic]

When would you like me to send this Dizzy Gillespie model 104 to you for a complete restoration including satin silver plating?

You clearly have a knack with these Yamaha disposable tubas.

IMG_0842.jpeg (56.67 KiB) Viewed 197 times

[bloke]

The small side of the bottom bow - prior to repair - was less than an inch thick.

[York-aholic]

Yep, about the same as this one, with small cracks at the both sides of the main (compound) crease.

It's in the mail, should be there in about 6 days.

Thanks!

[bloke]

............¹⁰