First aid for sticky rotary 5th valve?

[Steve Inman]

Miraphone New Yorker, reasonably new to me, previous owner used synthetic oil, as am I. 5th rotor worked fine in two Wednesday evening rehearsals, but hardly moves this morning, feels scratchy and very, very stiff, needs a lot of force applied right to the rotor "axle" to rotate it. Oil applied under the back cover, onto the "axle" at the top, and down the slide in both directions -- very little improvement.

What might the cause be, and steps to try to fix it?

Thanks!

[YorkNumber3.0]

.

[bort2.0]

Did you mix synthetic and regular oil? That gets gunny real quick.

In a pinch, pour hot/warm water in the mouthpipe and work it through the rotor. That helps with rotary horns, so I'm guessing a 4+1 would be fine too.

Or, did you overtighten the back cap when you put it back on? That adjuster screw will make the valve too tight to move if you adjust it too much

Never had this problem on my beloved old 1291. It's going to be a pretty easy fix for you or for a tech, just need to diagnose it.

Most importantly, DONT FORCE THE VALVE TO MOVE, you don't want to mess up the linkage.

And most importantly #2, show us the tuba! And where did you get it? I haven't seen a 1292 in years, and they are particularly handsome in lacquer. When I had my 1291, I tried lots of 1291s and 1292s, and had the 1292 leadpipe put on my 1291. There was absolutely no consistent pattern to which was best. There were some mediocre 1291s and 1292s, and some outrageous versions of each.

I do miss that tuba. So incredibly easy to play, and never one complaint from the other side of the bell. I sold because I thought the sound was about dull and colorless compared to other things (still agree with that), but I also sort of thought it mattered to other people or anyone else would care .. which they didnt

[the elephant]

Steve, did you (or someone unbeknownst to you) bump into the gig bag, maybe bending the rotor shaft at the stop arm just a tiny bit? Scratchiness and freezing can come from that, as well as a chunk of garbage inside the tuba. If you have oiled it more than the PO and have not had it chem cleaned it could be "detritus" but it also could be the rotor shaft where it meets the bearing. If you try to disassemble the valve and the rotor is difficult to pop out that may be the issue. Those two are my first to investigate when I have rotors with the issues you describe.

[bloke]

My main tuning slide started catching, and I found that all that had happened was something got in there somehow between the slide tubes and made some ugly little scratches. I think a couple of posts back about crap getting between the valve and the casing and making some ugly little scratches is a pretty good guess.

[Steve Inman]

THANKS for all for the suggestions.

Also ....

[quote=bort2.0 post_id=65420 time=1681665848 user_id=87

And most importantly #2, show us the tuba! And where did you get it? I haven't seen a 1292 in years, and they are particularly handsome in lacquer.

[/quote]

It looks something like this, and is intended as a replacement for my Conn 56J.

[Steve Inman]

Root cause -- corrosion around the spindle, which made the repair tech marvel that it had previously moved relatively freely.
All cleaned up and working fine, now. I will give this Wessex page a review and try to incorporate these recommendations moving forward.
https://us.wessex-tubas.com/blogs/news/ ... 0a3603c65d