King sousa finger buttons needed

[greenbean]

I have been playing my fiberglass King sousaphone a lot lately. It lives on a stand in my shop... so sometimes in the mornings... when I am supposed to be working...

I have realized that the finger buttons are terrible. They are CONVEX and overly small and, with the spring tension as high as it is, I often make a glancing blow and slip right off the button - flubbing that note.

What is my best bet for GOOD finger buttons?... Thanks in advance!

[the elephant]

The buttons on a current 2341 a huge (almost silly-big) and require specific-to-that-button top caps.

The sousaphone, SO FAR AS I KNOW, retained the old caps AND buttons, but now the tops are dished to be slightly concave, without a pearl. It is solid metal. These can be had in either lacquer or silver. They are the same size, which might not appeal to you, but the concave face might help you out with this while involving no surgery to your horn.

Alternatively, you could find someone with the current 2341 and ask to try one of the finger buttons and top caps on your old horn. I hate these super-wide buttons, but many here LOVE them. Again, they REQUIRE the matching top caps as the new style button will not be able to be fully depressed with the old-style caps.

Important to consider (and you could determine this if you get a chance to swap a set on, as I suggested) is I HAVE NO IDEA WHETHER THE STEMS ARE THE SAME BETWEEN THE TWO BUTTON/CAP SETS. The much larger ones might also require a stem that is longer or shorter than the old-style ones.

However, this is your best bet as the threads all match and the downstroke and upstroke resting positions are the same, so the ports will line up.

Unless something I don't know about has changed, which is possible. Again, locate a friendly owner of a current 2341 and try them out to see if they fit, including stem length, and upstroke/downstroke port alignment. (I think they are good.)

Best of luck, Tom!

[Three Valves]

I was looking for decent buttons for my Conn and gave up.

I may still resort to good old hot glue and aluminum/light foreign coins...

I was warned not to throw off the throw of the pistons resulting in misaligned ports.

Those things are a lot dinkier than I remember!!

[bloke]

@greenbean

Allied Supply/the Getzens (possibly due to having purchased all remaining F. E. Olds and Sons parts - in 1980) have some King-compatible 8-32 thread buttons that are also the same diameter as King (will fit perfectly into your King top caps' so-called 'donut spaces'), but feature pearls (though probably synthetic, but) which are nice and flat (since you make it clear that you don't care for concave touch surfaces. These buttons - obviously - are the old model O-99 tuba and O-95 sousaphone finger buttons.

They are part # A327 in their catalog.

An ALTERNATIVE would be this:
- Acquire a set of Olds O-99 tuba TOP caps - TOP VALVE CAPS - and not finger buttons (same thread as King) - from some repair-guy's junk box. Since you are in California, there may well be more of them floating around (out there) than anywhere else...though they tend to be everywhere.
Allied Supply CLAIMS that the Bach Mercedes (identical appearance to F. E. Olds) top caps are compatible to Olds ( part # S914), but I'm just not certain that the threading is exactly the same as Olds/King on the Bach Mercedes. IF...?? the threading is barely different, this would define hours of "tapping and turning" (annoying!) to fit them.
- Swap out the caps (duh).
- The Olds caps' geometry is different, so you would need to cut 1/8" off your King valve stems.
- Since the Olds top valve caps do NOT feature a "donut", you can install ANY darn buttons you like, as long as they are 8-32 thread...OR re-tap your (now: 1/8" shorter) King stems to the thread of whatever buttons you've found that you like (which would not only address the "concave" issue but also the "too small" issue.
(The Olds O-99 top caps WILL accommodate those huge "new-style" King 2341 8-32 thread finger buttons, but (geez) those things are HEAVY and - me...?? - I sorta prefer a lighter touch - with lighter springs...but this may not be an issue with other people. I'm also thinking that those huge/clunky King "tuba" buttons are concave as well, so...)

Based on the craftsmanship I've seen you display, I know that the "alternative" suggestion (were it that you found it attractive) would not be any sort of problem for you to execute.

worthy-of-reading post script:
The Yamaha 621 3/4-size profession series tubas feature finger buttons that are large (about the size of a quarter), lightweight, metric (M4x.75) threading...which is not all that far off from SAE 8-32 threads, and ALSO feature FLAT - and genuine m.o.p. - pearls. You could either re-tap/chase your King stems to the metric thread, or (carefully/slowly - working each button back-and-forth) "muscle" the Yamaha metric buttons into the King SAE stems.
The Yamaha button's part number (to be bought through some repair-guy friend or Yamaha dealer) is H6141001. The Yamaha parts whse is ALSO in California, fwiw.

[greenbean]

Thanks to all of you for sharing so much good info. I am definitely looking for the "path of least resistance" type of solution. And I realized that the finger buttons are convex because of the m.o.p. pieces are convex. They have been deliberately given a curved shape - it not from wear. I checked the finger buttons of the OTHER King tuba sitting in my shop - 3 feet away - and, whoa, it has buttons, too! It is a 1939 King in silver-plate and 2 of its buttons are the same King-button-with-orange-lacquer that my sousa has. But button #3 is different and perhaps original: silver-plate and slightly different design (the knurling is at the top edge rather than in the middle of the button) with the same threading and similar m.o.p. - but which is FLAT. The button is actually a bit smaller in diameter than the sousa buttons but feels better. Maybe what I need to do is replace the m.o.p. bits to solve my problem!...

[Kirley]

Hey, Tom.
I've got a set of 4 of these King sousa buttons.
They're slightly concave.
Not sure if that's what you're looking for but you're welcome to try them and then we can work something out if you want to keep them.

[greenbean]

Thanks for pulling those out, Luke! I will be checking out some MOPs at my techs later today. He thinks he has what I need. We will see. I have played on the ones that you have. I actually wasn't too crazy about them. I think I like flat ones - the ones on my Yamaha 321 Eb are perfect.

[Matt Walters]

Chuck the finger buttons up in a lathe and machine the finger pad area flat. Leave a little roughness on the surface and you are set to go.

[greenbean]

Chuck the finger buttons up in a lathe and machine the finger pad area flat. Leave a little roughness on the surface and you are set to go.

Thanks, Matt! This is exactly what we did yesterday. Worked beautifully!