so this is happening:

[P@rick]

It was not trying to contradict the vibration theory. I should have written “play it out” instead of “blow out”. The vibration theory makes sense. The air flow is indeed very limited, but not completely excluded I think.
In my case it was clear that “legato/ppp” pieces did not move the slide (or almost not), but “fff/sfz/>” pieces did move the slide.

[bloke]

It was not trying to contradict the vibration theory. I should have written “play it out” instead of “blow out”. The vibration theory makes sense. The air flow is indeed very limited, but not completely excluded I think.
In my case it was clear that “legato/ppp” pieces did not move the slide (or almost not), but “fff/sfz/>” pieces did move the slide.

perhaps a combination...??
It's happening with extremely loud playing during very exuberant sounding or "Rock and Soul" types of Christmas tunes being played, where - unlike classical music - I'm playing loud loud loud (relentlessly).

...The same thing would surely happen during a performance or rehearsal of 1812, etc.

[iiipopes]

Two observations:
1) Expanding the slide a thou so it has more friction, that would still be a "brake" without screwing up the alignment; and
2) My 2nd valve slide (now that the community band season is over until late January) is with my tech having a water key installed, as I also put so much air through the tuba (being the only regular tuba player, including being the only one at the last concert), condensation collects in the 2nd valve slide as well as farther downstream.

[bloke]

Slide expanders are crude tools that ruin tubes.
=========================
I have to work frantically (because I have a customer arriving - now - in about five minutes, and in two hours I need to be clean/dressed/leaving for a gig (because I have two stops on the way to the gig, thanks to Mrs. bloke).

...so here's the slide brake.
The lever is right where I grasp the main slide to remove it.

ALSO...
I plugged up the inconveniently-positioned oem water key drain hole, and moved the water key over so as it drains in PLAYING position.

[Mary Ann]

So did it work?

[bloke]

So did it work?

yes, but how could it not?

...and even though I used this instrument at the rehearsal a few nights ago, I decided to take the compact Holton B-flat to the show tonight, because everyone is so packed in on the stage and also there are a couple of rock and soul numbers where a smaller instrument with a more gritty sound and the ability to cut the sound off quicker works out better.

[bloke]

I suspect that what is not understood is that both of these pairs of tubes already fit just about as nicely as pistons in their casings. If they don't quite fit that well, the fit is close to that. If I expand the inside tubes - wrecking their nice machined condition - they won't slide anymore. The tolerances are already so close on each of these pairs of tubes that - when I first put this back together after constructing this contraption and replacing the water key with the one seen on the picture - the slide wouldn't slide in, and all it was was a tiny little amount of dirt on the small side outside tube. Further, I just didn't want to intentionally wreck the alignment of a slide which I went to a lot of trouble to align perfectly.
@the elephant , I suspect, either gets this, or gets it and ALSO thinks I'm being pretty silly.

[iiipopes]

Slide expanders are crude tools that ruin tubes.

Thanks for your explanation. I understand better now.

[bloke]

crappy picture, but I shined it up and shot clear on it.
(didn't want to take the "slide brake" back off to polish it, because it's awkward and requires Mrs. bloke's help to get it back on - particularly without scratching lacquer, so I had to do some careful 'round-the-edges buffing...)



There's still more stuff to do to this thing, but the list is getting shorter.

[bloke]

OK...So this FINALLY stopped the slide from moving (when blowing the friggin' crap out of this thing)...

...so yes: I guess it IS air that's causing it.

EVEN AFTER installing the "slide brake", the slide brake's rubber pad would just scoot across the nice smooth lacquered surface...

...so I found a new/old REALLY COARSE belt sander belt, cut a rectangle out of it, and contact-cemented it to the outside slide tube.






That FINALLY stopped the sliding-when-I-blow-the-crap-out-of-the-tuba thing.

I was going through ______ Symphony No. _ (which is rumored to be programmed - next year - with one of the freeway philharmonics with which I'm associated). I've played #_ and #_, but never #_ (other than a single movement), and having a crack at #_ is an exciting proposition.

(sorry...but - just like fb - fack chekkuz have censored my post as - since the '23 - '24 schedule hasn't been released - it may only be 97% true.)

Anyway...I was blowing through a loud-as-hell passage in mvt. _, and (sho-nuff) that damn slide was OUT a friggin' INCH and was crackin' the damn pitches in the mid-upper range.
JETSON !!! YOURbbbbbbbbb FIREDbbbbbb !!!!!!!

PLEASE, Mr. Spacely...It's the DAMN SLIDE !!!

[kingrob76]

I'm actually curious - was this latest example at home? It would remove the riser variable, if so.

[arpthark]

Gives me an idea: now you can market these slide brake things as Sellmansberger's Sprockets.

$279.99 + s/h

[Mary Ann]

OK...So this FINALLY stopped the slide from moving (when blowing the friggin' crap out of this thing)...

...so yes: I guess it IS air that's causing it.

Told ya so.

[bloke]

Told ya so.

[cjk]

https://www.thomannmusic.com/yamaha_sli ... rumpet.htm

adaptable?

i envision a rod with a thumbscrew. unscrew the thumbscrew, pull out the slide kinda like how the very bottom of the main tuning slide was on my piggy.

[cjk]

well I SUPPOSE it will actually fix itself IF you let it fall out on the floor a few times.

[bloke]

With the sandpaper, it works perfectly.

Again, I want to be able to grab the slide and pull it completely off without dealing with anything more than a lever that's right there by my thumb, and that's what I have.

On the #1 slide, I am going to install a "Bach #3-style" steel stop rod with threaded nuts and very small O-rings, because that one doesn't need to come off, but also slides effortlessly, and I've had some close calls with it when setting the instrument on its bell.

There are quite a few things that I usually do to instruments - after buying them - in order for them to completely suit me.
If there's something that distracts me - whether it be a tuning issue or something mechanical - I'm going to be striving to address or eliminate it, because I just don't like to be aware of tubas when I'm being paid to play music. I guess they're paying me to play the tuba, but they're really paying me to play music.

I've seen some little factory-installed black leather straps and buttons on some fairly pricey instruments, but I think I can do better than that.

[Mary Ann]

I did not steal your quote, Peterbas. I myself, if you go back and read, told him that he was blowing so hard that he scared it enough to drop its pants. Perhaps you said the same thing, but I said it independently.

[bloke]

I like it.

an argument over which one first made fun of how nicely bloke aligned his main tuning slide, and how a problem was solved without ruining nearly perfectly-assembled machinery


bloke "a lowly fixes-horns-on-Christmas-Day/3D-world/bas-humbug type of guy"

[bloke]

There's a lot of good-natured chain-jerking that goes around here, that is sometimes misinterpreted as being annoyed (or whatever).

"ACTUALLY arguing over tuba crap" - pretty silly

As long as we stay away from libel, I think we're good...

... so what happened to that current two-month self-suspension...??