Grotty strings

[Otto]

I've just got round to getting my Mum's piano tuned (1985 Knight K10) after being in storage for a year and acclimatising in my place for 6 months.

The tuner said the strings have corrosion on them, and he's right - you can see it in places on some of the strings. Apparently it makes tuning the strings almost impossible due to errant harmonics. Rather than offer to clean it off he wants me to do it between now and when he next comes.

What are the recommendations ?

Toothpaste ?
T-Cut ?
Brasso ?
Wire wool ?
File ?
Pneumatic drill ? (seems a bit drastic mind)

Awaiting your suggestions with bated breath ...

[tuna]

Fine to very fine wire wool. When working on the top of the bass strings, clean with a downwards motion only if an upright, and away from you if a grand.

[vernon]

As Tuna says, 0000 wire wool but I would also add WD40 sparingly to the wire wool and wipe off any surplus. Obviously don't spray it onto the strings,rather the wire wool.Also make sure none reaches the wrest pins.

[Barrie Heaton]

I believe your tuner is referring to the treble strings being very false and any method used will not remove the the pits on the string at the back nore at the termination points

using wire wool on the stees will make them look nice to the eye but how are you going to clean the back of the string or the termination points and you are removing mass from the string casing more problems

if the string are so pitted that it is making the piano un tunable restring is the best option

Barrie,

[Otto]

I've probably exaggerated the problem. Now the piano's been 'tuned' it is there or thereabouts. To my ear, some of the notes are slightly 'pub-piano-ish', which they certainly were not when it was new.

The tuner's real complaint was that he could hear harmonics which shouldn't have been there (your description as false), and they didn't exactly help matters when trying to match up the octaves.

Fairly obviously the strings will sharpen marginally if I take wire-wool to them, and it certailny won't be uniform. So I'm planning to do this in about five months time, shortly before the piano is to be tuned again. As for getting to the back of the strings, short of hiring a leprechaun, I don't think that's on - but I ought to get to two-thirds if not three-qaurters of a string.

I am surprised that pitting at the termination points would have much effect as they are by definition forced nodes at every frequency. Why does it ?

[Barrie Heaton]

I've probably exaggerated the problem. Now the piano's been 'tuned' it is there or thereabouts. To my ear, some of the notes are slightly 'pub-piano-ish', which they certainly were not when it was new.

sound more of a voicing problem

The tuner's real complaint was that he could hear harmonics which shouldn't have been there (your description as false), and they didn't exactly help matters when trying to match up the octaves.

quit4 often when you tune the unison in most of the falseness is masked

Fairly obviously the strings will sharpen marginally if I take wire-wool to them, and it certailny won't be uniform. So I'm planning to do this in about five months time, shortly before the piano is to be tuned again. As for getting to the back of the strings, short of hiring a leprechaun, I don't think that's on - but I ought to get to two-thirds if not three-qaurters of a string.

rubbing down the strings can help the tone in some cases but over use can make it worse

I am surprised that pitting at the termination points would have much effect as they are by definition forced nodes at every frequency. Why does it ?

The termination pints are very important to the tonal quality of a piano, bad termination pints make the string very false in octave 6 and 7 the change for nodes to ant nodes is very small. The top bridge termination point is fixed and yes forced nodes are present to a point however, the soundboard bridge termination point is not it moves, because of the movement of the soundboad the termination point move as well. Also, the hammer striking the string will alter the termination point of the top bridge. The main culprit is longitudinal movement of the strings which can make phasing with with the overtones and the harmonics if the movement of both bridges are not in the design prams


Barrie,

[vernon]

What are the physics of termination points in the piano?
Logic suggests that they should be knife sharp not of a rounded section which must give an infinite number of termination points as the string moves with vibration.
Obviously this doesn't seem to provide a problem and a knife edge would efficiently soon chop the string off.
TPs are generally just a cleaned off part of the casting with little apparentmechanical accuracy. Some of the older ones which are brass rods surely are too soft.

[pianotechman]

If you do clean the strings with steel wool, please dont be tempted to use any liquid metal polish,. especially on the Bass strings. I went out to a customer once who had, and the tone of the bass strings had been totaly destroyed. You should be able to purchase a special 'carborundum' rubber from the piano suppliers to clean the treble strings, that is made for the job!

[Openwood]

I don't mean to sound unreasonable, but I don't really understand why the tech won't do it for you. Isn't this precisely the sort of specialist service that you pay him for? Problem = piano sounds bad; Solution = hand over some cash to a professional to make it sound better. In your position I'd be tempted to get another tech in to quote for the whole job and see how it compares with Mr Do it Yourself.

[Barrie Heaton]

I don't mean to sound unreasonable, but I don't really understand why the tech won't do it for you. Isn't this precisely the sort of specialist service that you pay him for? Problem = piano sounds bad; Solution = hand over some cash to a professional to make it sound better. In your position I'd be tempted to get another tech in to quote for the whole job and see how it compares with Mr Do it Yourself.

So he can say "You made a right mess of that....... " Sharp intake of breath "that's going to cost to put it right govna "

Barrie,

[Openwood]

"that's going to cost to put it right govna "

Ah, but of course! Altogether now, "Oh, it all makes work for the working man to do"

I just wanted an excuse to use that smilie. Incidentally, I once covered a Year 7 English class for an absent colleague and thought I'd done a pretty good job for a non-specialist. I later found out the kids had all gone home convinced that a small yellow face was a device used in speech and literature to draw a comparison between two dissimilar objects

[pianotechman]

[


So he can say "You made a right mess of that....... " Sharp intake of breath "that's going to cost to put it right govna "

Barrie,[/quote]


Probably the sort of self- styled technician who also doubles up in a trade in surfacing drives and Block paving Barrie!....or expensive brand car sales come to think of it!

[Openwood]

At the very least if he asks for a cup of tea I'd reply that I'd be delighted to offer him one, provided that he supplies a tea bag, a mug, some boiling water, milk and sugar,mixes them together, rinses the cup afterwards and puts it back in the cupboard, thanks awfully.

[Pianomate]

Hi. Does anyone know where you can purchase the "carborundum rubber" suggested as I have been asking about with no luck. I know you can buy something called a "bath rubber" from the plumbers merchants for polishing defects out of enamel baths. Perhaps this is the same thing with a different label?

[vernon]

we use what used to be called an "ink rubber" available at all office supplies a few years back. It's like a pencil rubber but coarser. Don't know if you can still get them now. Few people use fountain pens now.

[Pianomate]

I've found them in our office supplies catalogue - £10 for a pack of 20 - Will get some and try.

Thanks

[vernon]

Jolly good.
Lionel who was our Head Technician always used them at Steinways before he went up market and came to us!!!

[Pianomate]

Chatting to a tech today, he says he swears by a "Cramer Bath Rubber" for cleaning surface rust on grotty strings. They are sold to clean stains of enamel baths and you can get them from plumbers merchants.