Bending a nickel silver paddle

[sirisobhakya]

An old Bach 50B3L of my former school has a Gb paddle rod/linkage that makes the Gb valve barely usable. The horn has been serviced once and it look like the repair shop did a botched repair on the linkage. The paddle piece is long lost, and all that remains is a long rod that the paddle piece slides onto. The rod is now longer than original, and the angle is almost parallel to the slide receiver. On engagement, the rod would touch the receiver. Although the valve is fully engaged fortunately, the almost-parallel angle and the excessive length of the rod leaves no room for any finger holding the horn. For me who have a large hand and can bend my wrist a little and use my palm to support the horn, it is just uncomfortable and reduces my agility in using valve, but the girl who normally plays the horn has no chance. Although she has been using the horn for almost 3 months now, she has never used the Gb valve once. I shall upload the image of it if I have a chance to take it.

The ways I can think of to fix it are: 1. cutting the rod to make room for ring and little finger, or 2. cutting plus bending the rod outward from the receiver, and angling it up so it clears the fingers and also leaves the rod for if we can find a replacement paddle piece in the future.

But how hard and how brittle Is nickel silver? Can I cut it or bend it with simple tools, or should I take it to a tech (which is a bit hard because the horn is in use, and the school's reimbursement process for repair cost is lengthy and difficult, and the band director don't quite want to get into it if not absolutely necessary).

Any other suggestion is very welcome. Thank you very much.

[ghmerrill]

Bending the rod can be quite tricky and require a LOT of trial and effort. Don't try to do it on the horn -- take it off to do the bending. If you try to do it on the horn there's a high chance that you'll break the swivel bass in one way or another, or break the pivot tube tube that the bolt/axle goes through. Besides, there just isn't a "one size fits all" approach to these rods and paddles that works. I don't know why makers have (in general) continued to use non-adjustable valve levers. Added expense I guess -- make the customer pay for the customization.

You might consider doing what I did. Cut the rod fairly short and add an adjustable extension of some sort to it. This offers a couple of advantages: You can experiment all you want with bending and adjusting the extension portion itself without endangering the rest of the lever or its base. And you can then quite easily replace the lever extension for a different player -- or tune it to your heart's content over time. Here's a picture of my 2nd valve lever. It puts the paddle in perfect position for me. Yes, that's on old 5 centime French coin as the paddle. The usual paddles are way too big (intended, I suppose, as another substitute for an adjustable mechanism).

All I needed to do this was that aluminum sleeve from the local hardware store and a piece of brass rod. Then I drilled and tapped some holes in it for set screws. Plus the 5 centime coin, of course. Depending on the diameters of the lever and the sleeve, you may need to sand down the lever rod or the extension rod. I think I used 3/16" rod for the extension. Even if you have to buy the tap and bit for it, the cost is minimal. Depending on the original lever rod and it's position, you MAY want to bend that to a somewhat more convenient location for adding the extension. But that's a one-time task since it doesn't have to be exact (done OFF the horn and then reassembled). After that, all your work is with the extension.

[whitbey]

Metal does not bend without annealing and then hardening. You need a good tech that can do that kind of work and also make a new part when they break it.

[ghmerrill]

Metal does not bend without annealing and then hardening.

This is way too much of a generalization to be true.

[CharlieB]

Yes, you can cut and cold bend a nickel-silver rod with simple tools.
Heat bending nickel-silver is not recommended, as it may crack.
There is no silver in nickel-silver. It is an alloy of (mostly) copper, nickel, and zinc.

[sirisobhakya]

Update with pictures.

The rod is quite thick I am quite afraid it could not be cut cleanly. Any modification/repair suggestion?









From the last image, you can see that there is no space left for any finger when the rotor is used.

[Bonearzt]

Chaichan, that square rod is actually quite easy to bend as it's fairly soft.
Care is definitely needed, but if you support the rod on the valve side of the pivot, you can press the finger side toward the mouthpiece to where you need it. But you MUST support the rod on both sides to reduce the strain on the lever mount as much as possible!

No need to heat or cut!!


Eric

[ghmerrill]

Eric is definitely right about this. But if you have't done it before, there's still a significant risk of messing up the rod pivot tube or the pivot base (don't ask me how I know). If you manage to twist off the pivot tube from the rod, then you're really screwed (and waiting for a new part to arrive).

I'd take it off, bend it, put it back -- repeat as necessary. Of course, that means that you'll have to manage to reinstall it with the lever spring -- which can be one of life's most frustrating experiences (but a good skill to acquire).