Jinbasso rotary valves replacement

Repair and modification discussion
Post Reply
User avatar
emcallaway
bugler
bugler
Posts: 139
Joined: Wed Nov 05, 2008 10:42 am
Location: Norfolk, VA

Jinbasso rotary valves replacement

Post by emcallaway »

Inspired by Bloke's amazing cimbasso build I would like to try something similar but a much smaller in scope.

I am reasonably happy with the playing characteristics of my cimbasso but the 5-year-old Chinese rotary valves suck. A lot. I believe that at least one valve was mis-machined, they all have an unreasonable amount of vertical play (click click click click), and generally are demonstrating a lack of proper fit and finish. The horn would be a joy to play if valves worked as smoothly as (for example) Miraphone valves and I'm presently deciding between doing a rebuild of these valves and a full replacement.

Price is a consideration, but certainly not a constraint. I would rather drop some $$$$ and have a better instrument after it is all done. :tuba:

So the question then is this: where can I find replacement American-made or German-made rotary valves and casings that are approximately the same bore (0.725) as the Jinbao cimbasso valves? How much will the parts cost and who should I contact to order such a thing? ...or is there a common donor horn I can nab off fleabay for the valves?
Ace
5 valves
5 valves
Posts: 1395
Joined: Fri Mar 19, 2004 12:46 am
Location: Berkeley, CA

Re: Jinbasso rotary valves replacement

Post by Ace »

Of the many rotary-valved horns I've owned, by far the best was the Cerveny 601 CC. Very stable, quiet valves, smooth as silk, no sticking or hang ups. Stood the test of time. I wonder if that company makes their own rotors. Maybe something you could buy from them.

Ace
User avatar
emcallaway
bugler
bugler
Posts: 139
Joined: Wed Nov 05, 2008 10:42 am
Location: Norfolk, VA

Re: Jinbasso rotary valves replacement

Post by emcallaway »

That's a good thought. Unfortunately Cerveny F and Eb tubas are all .709 bore and all of their CC and BBb horns seems to be .787 and up so it doesn't appear that they have anything in the sweet spot for me.
User avatar
emcallaway
bugler
bugler
Posts: 139
Joined: Wed Nov 05, 2008 10:42 am
Location: Norfolk, VA

Re: Jinbasso rotary valves replacement

Post by emcallaway »

I have found several boutique brand F tubas that feature an 18.5mm (0.728) bore that would probably be close enough. However, I suspect that it would be cheaper to buy a name brand cimbasso than to buy a set of valves intended for a five-digit horn.
User avatar
emcallaway
bugler
bugler
Posts: 139
Joined: Wed Nov 05, 2008 10:42 am
Location: Norfolk, VA

Re: Jinbasso rotary valves replacement

Post by emcallaway »

You have my curiosity piqued. Once the blokebasso is in production I will gladly look into upgrading to it.

In the meantime I've done some work on the existing rotors to keep them limping along. Still looking for some 18.5mm replacement valves.
User avatar
emcallaway
bugler
bugler
Posts: 139
Joined: Wed Nov 05, 2008 10:42 am
Location: Norfolk, VA

Re: Jinbasso rotary valves replacement

Post by emcallaway »

The factory already solved the problem of adding resistance through strategic valve misalignment. :lol:

That's a good suggestion, thanks. There are lots more affordable options at 18mm.
Ace
5 valves
5 valves
Posts: 1395
Joined: Fri Mar 19, 2004 12:46 am
Location: Berkeley, CA

Re: Jinbasso rotary valves replacement

Post by Ace »

[quote="emcallaway"]The factory already solved the problem of adding resistance through strategic valve misalignment. :lol:

Ha. I love it.

Ace
Post Reply