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I have a piano I would like to restring. The wires are full of false harmonics and must be replaced but the wound strings are still satisfactory. I just can’t afford a new set anyway.

I would like to re-use the wound strings again. Any comments?

I’m particularly interested in suggestions as to how I can safely restore the colour of the strings. I know metal polish will clog them up.

Thank you!

A long time ago, poor me used to boil electric bass strings in a pot and reuse them. I don't know about that with pianos.　:D

Thanks Pro-TAC.
I would not have thought of that. As long as they’re dried thoroughly and quickly I doubt it would do any harm, but would it get the tarnish off?

Get some small, fine grade wire wheel brushes.
Attach to a drill or dremel tool.
Remove the action.
Brush the length of the strings, holding the wheel perpendicular to the length, parallel to the winding coils.
[You'll hear amazing sounds!]
Loosen and rotate the strings 1/2 turn and repeat, polishing the bottom surfaces which now face up.
This will polish the strings, but more important, it will remove the corrosion and allow the strings to flex and sound freely.
It's much more effective than the traditional "roll the knot" method.
Credit goes to Bill Bremmer.

Have you tried replacing just one plain wire trichord - the strings of just one note? If not, I think it would be worth trying. You might discover that it doesn't make as big a difference as you expect.

Restringing is not just a matter of replacing the wire. Other things have to be addressed; the profile of the V bar and/or condition of agraffes, and the condition of the bridge pinning and the bridge itself There are comments about this from two experienced rebuilders on the Strings & Stringing page of my website.

In most cases, it is cheaper to replace the piano than to replace the strings.

That’s why I want to keep the existing strings. I’ve done the cost benefit analysis... short of dragging the piano into the yard and burning it, even scrapping has a cost. It has many fine qualities, other than the worn out wires. The action is excellent, and the keys Ivory. Anyway, it’s mine, and I’ve owned it for 20 years.

In this case it’s the wires, David. I’ve only restrung about two dozen pianos in my life, but I have never found it did not make a profound difference. You’re expert is quite right that inharmonicity can arise from other causes, but agraffes and bridge pins are often still in good condition. The piano dynamics are very good so I don’t think the crown is gone.

Thanks for your link, though. I’ve read the article, but don’t agree with everything in it. It just doesn’t fit with my experience.

I also think that taking the high road may be technically ideal, but there is a difference between renovation and conservation. Having said all that, if this piano belonged to a customer I would be telling them that the cost of restringing outweighs the value and for the cost of restringing they could buy a better instrument.

However, if they insisted that they wanted this piano restrung, I would not hesitate to assure them the aural result will delight them. Please bear in mind, I have considered all the issues raised in your article with respect to this piano. The bearing and anchor points are in my opinion not the problem.

Thanks Ed.
Yes - I don’t like rolling the knot. I have known it to result in buzzing strings, and also it’s not very effective.

I guess the grade of wire brush is important. I would be worried about wearing away the copper. Have you actually tried this?

🤗

In my 50 year experience servicing and rebuilding the finest pianos ever made; I can find very little to blame in plain wire for false beats.

V-bars shaped to a true V shape, with the metal of the V-bar properly soft and naturally lubricious, (some manufacturers case harden the cast iron and this is damaging to the wire and tone). Laying the wire into the piano so as to avoid any twists and so the natural curve is placed identical from note to note. Making sure the string alignment follows a straight line from hitch to tuning pin, (allowing for bridge pin offset of course). No overstretching of the wire during the stringing/tuning process. Precise placement of bridge pins so as to insure they are tight in the holes and the bridge cap wood is strong. And the final revelation, bridges configured to reduce the ability of Longitudinal mode energy to mix with the Transverse mode energy.

I have come to the conclusion that a significant number of treble false beats are mode mixing between L and T modes because when I modify bridges that have high false beat problems to reduce their ability to mode mix, the false beats go away. And because when I have done all the above work except reducing the bridges ability to mode mix, some false beats remain with the piano in the same exact notes with the same exact rate.

I can see this method helping the tone and liveliness of the bass strings to an extent.

I personally have tried the loosening and twisting a few turns in the direction of the windings, without much (if any) improvement; some, maybe. The way I see it, if you are going to loosen the tuning pins, it may be best just to go ahead and replace the bass strings.

When replacing bass strings with new, the twisting method did work to an extent, to get a good tone with the new bass strings. Some string manufacturers recommend/suggest twisting the new bass strings and some don't.

I've also read that you can remove the bass strings and soak them in ammonia and reinstall. But, again, that is a hazardous chemical, and a lot of work when new bass strings wouldn't cost that much more for the same amount of effort.

Rick

Thanks Ed.
Do you think false beats can be caused by stiffness in the wire? I have heard a theory that when a piano stands for a long time at a low pitch (eg A=435) the wires stiffen with age. If the piano is then raised to standard pitch, the wire at the bearing points does not adapt to the new position because of the stiffness. Consequently, depending on various factors, the wire has an indeterminate length, obviously causing indeterminate pitch.

Does that make sense to you?.

voodoo science, stiffness in the elastic region is determined by Young's modulus, which is about 200GPa for steel, and that's for any type of steel, and it won't change no matter what you do. Something like work hardening changes the properties of steel, but not in the elastic region, which is where the strings always work (otherwise they would not hold tuning and would break)

Strings do get work hardened where they first start to wrap around the tuning pin after being tuned enough times and if the scale length places the wire at a high enough percent of the break strength.

Wire can get abraded flat at the V-bar when the V-bar is case hardened cast iron and/or the casting is made in such a way so as to place the carbon in the casting in a harder form than graphite.

As far as wire sitting below pitch for many years, I don't think that would cause any falseness. More likely the wood of the bridge is not holding the bridge pins firmly enough.

Hampshire piano has some videos on YouTube about cleaning bass strings with household ammonia. https://youtu.be/mBwaibt2d3M I tried it on an old upright, and was pleased with the results. Works with copper wound strings, but iron wound would require a different approach. I had earlier tried the brass wire wheel approach on a different piano, but apparently my brass wheel wasn't fine enough, and I ended up damaging some strings.

Very important to clean and dry them very well and very fast after that.

The rinsing and drying protocols are all clearly presented in the video series. This is what made me inclined to give it a shot.

Yes, with remarkable effect on an 1880's Mathushek upright. I used brass wire dremel brushes.
It's very easy since you don't remove the strings. You could try this on a few strings and if not happy, try the ammonia, boiling, etc.
The spinning brush sets up a strong vibration in the string which knocks out the corrosion between the coils.
In new bass strings the copper coils move past each other. In corroded string they are stuck together, which kills tho higher partials and damps the string.