using O-rings as slide silencers

[bloke]

Others may have better luck with the things that people traditionally use, but I don’t have very good luck with c. 2mm thick round O-rings - which are sized to the tubing outer diameter, and neither do I have good luck with similarly-sized square-profile O-rings.
Both tend to be able to be pushed past either the outside slide tube - or past the slide ferrule - fairly easily.

Something that seems to work better - at least, for me are very small undersized O-rings - and of much smaller diameter- that I have to work pretty hard to stretch over their slides. Those actually seem to be more likely to stay in place, and are more resistant to jumping over the outside slide or the ferrule. …To describe these best would be to say that they are more the size that someone would probably select to use on trumpet slides.

Many years ago, I bought a new Miraphone model 88 that someone else had special ordered (and rejected… not the best 88, I should have passed on it as well but whatever…) with a left-hand fifth slide trigger and a left-hand operated fifth valve. The fifth slide ferrules were factory precision-fitted with fairly substantial nickel silver flat washers that were wide enough to support an O-ring without allowing it to get pushed out of position. That was the only instrument with which I’ve ever used regular 2mm diameter approximately 3/4 inch inner diameter O-rings (whether round or square profile), and had them never jump out of position.

[the elephant]

On my 186 I use square cut 14 mm rings that are 1 mm square. They stay in place pretty well. I might switch to slightly smaller ones.

Years ago I had some made of a very soft plastic that did not stretch. A local friend with a lathe turned them for me from a short rod of whatever the material was. It worked better than anything I have ever used. And he passed away a few years ago, so I likely will never know what the material was. It was not Buna N, nitrile, Delrin, or ABS. It has a rubbery feel but again, it did not stretch. They were made to be just a bit tight, and I had to install them greased. They were very quiet and never popped loose.

The Buna N (the 3rd Reich's famed "synthetic rubber" — my grandpa bombed a Buna N plant in Weiner Neustadt in 1944) and Nitrile rings that are so common today are really soft and stretchy. In the old days, I used stuff labeled as "rubber" and it was great, but it would get hard and eventually break in half if you had to remove them. I think I would rather have that old-school rubber and just keep changing them. The well-stretched modern stuff, even when stretched quite a bit, still are able to walk over the ferrule or outer tube end. I need to talk to a lumber friend to see what he can recommend.

Anyway, yeah, same experience here, and I also use overly small rings to improve that annoying behavior, and no, it does not completely work.

Better Things for Better Living...Through Chemistry
— DuPont, 1935

[bloke]

Again, with outside slide trim rings + precision turned washers that butt up to ferrules, any of those shapes and sizes of O-rings will work without fail.

As an example, if some tuba features a 19mm bore - and the outside diameter of the inside slide tubes is 20mm, some washers that are precisely 20mm on the inside (and with a nice flat 1/8-inch surface sticking out horizontally) will keep most any of the previously mentioned styles/sizes of O-rings from creeping up on the ferrules.

Those washers could be lead-soldered in place, but the ones that Miraphone (made for that special-ordered model 88) fit so nice and closely that they just stayed in place, and the O-rings held them in place.

Of course, these washers could be cut out of 1 inch diameter nickel-brass or yellow-brass round bar stock, but who knows…?? McMaster or someone like that might already offer some washers that almost fit, and someone could sit and watch TV - round file in hand, and hand fit some (that already almost fit) to their instrument.

Here’s the real issue:
Fabricating washers like this is just a little bit of trouble, and the O-ring problem probably isn’t quite enough of a problem (at least, I don’t think I’m going to go to this much trouble) to go to this much trouble to solve it.

(I am reminded of the Miraphone-made washers - from time to time - when playing my Holton B-flat tuba that I just fix up for myself last year. The #1 slide stays in the same place for just about everything, except I push it in - all the way - for 5th partial C and B-natural tuning.)

[iiipopes]

I have tried them on and off for over forty years: trumpets, tubas, anything else prone to moving a slide to help tone/intonation. For me, the inevitable deterioration wasn't worth the cost or effort to keep replacing them. Nobody has ever called me out for a slide clanking.

[bloke]

I have tried them on and off for over forty years: trumpets, tubas, anything else prone to moving a slide to help tone/intonation. For me, the inevitable deterioration wasn't worth the cost or effort to keep replacing them. Nobody has ever called me out for a slide clanking.

Me neither, but I call myself out for extraneous noise, whether valve noise, slide noise, or even that really disgusting “inhaling next to the mouthpiece” noise (that I’ve heard on youtube/fb recordings).

People don’t tend to call others out for chewing with their mouth open or talking incessantly or too loud, but they also don’t invite them back to subsequent dinner parties.