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I am helping a friend that has started an Instrument Exchange program in my town. The instruments are donated and given to deserving students who don't have the financial means to purchase or rent an instrument on their own. This program started a few weeks ago and to date we have over 25 instruments.

I have volunteered my services to clean and make minor repairs, where needed. I am working on a small helicon that has a bent stem on valve 3. I have limited instrument repair experience, but very handy (might not be a transferrable skill).

I am hoping that an experienced repair person can provide some guidance on the best method of repair. The exchange does not yet have a large repair budget and some of the instruments are not worth much, so we are looking for a workable (read: inexpensive) solution.

The horn is a Eb helicon made by a company named D Ansingh and Co, model Soloist and the medallion has the word Zwolle.

Thanks for you help...

It SHOULD be relatively cheap to have repaired or you can have a replacement made for not too much money.

PM sent.

I make valve stems fairly regularly when needed by a local repairman. The ones I have seen all unscrew.

I would NOT suggest putting it in the casing and tapping on it. You're likely to break it off at the valve, or worse. It has already been stressed at least once to be bent like that.

The valve stem should be straightened almost like you would straighten a bent nail.

First, I would unscrew the valve stem from the piston. Then find something solid to support the valve stem while rolling and hammering.

When the stem is straight, screw it back onto the valve and carefully seat the thread against the top of the valve. The newly straightened stem will probably be cockeyed because the top of the valve will have been bent during the accident. Holding the assembled parts in your hands, carefully push sideways on the valve stem until no longer cockeyed.

Good things for supporting the valve stem during hammering: (a) anvil; (b) bench vise

Protect the valve stem from scratches by (a) laying down a piece of cardboard from a cereal box or shoe box and (b) hammering with a soft-head hammer.

What to avoid: (a) Hammering near the top of the valve stem (where the female threads are) because it is too easy to accidentally smash in the sides of the valve stem and compress the internal threads. Do not rest the top of the valve stem on your support surface for the same reason; (b) Damaging the piston (which usually is made from very thin metal) by tightening down on the piston with a vise, pliers and the like, or by hammering on the piston.

I wouldn't....

What Doug Elliot and bloke say. This is nothing like straightening nails. With a bend comes metal fatigue. It has to be unscrewed and re-annealed before trying to straighten it, and then it can be determined whether or not it can be straightened, or the economy of time and effort is simply to lathe a new part.

Nails are made out of soft iron to begin with, and nobody cares if they fatigue -- until the head breaks off some years down the line, then everybody cares a lot, but doesn't bother to ask if straightened nails were used.

Considering all the differences of opinion on how to do this job right, it might be best to put this piston into a USPS flat rate box and send it to someone to straighten it and, if a disaster happens (like the stem snaps or the piston top collapses), the repair person is prepared and able to fix that problem, too. This isn't something that should take hours of work no matter what needs to be done so probably not too expensive.

Some things are best shopped out...

Have you priced a local repair guy yet?