Servicing the Playing Mechanism of Your Piano

It is very important to not only have your piano tuned by a certified technician, but also to look after the action “playing mechanism” of your piano.
Have you ever opened up your piano at the top, and looked inside, just to wonder what really is going on inside there?
Well … That’s the action of the piano, almost like the engine of a car.
It consists of hundreds of parts, made from wood, felt and brass., although some piano manufacturors make some parts from plastic.
Plastic is not a good material to work with, especially not in pianos, because with age, they crumble or break apart.
Carbon fibre is also used these days, which I think yields good results.
Let me quickly introduce you to some of the parts:


The hammers are the felt-covered parts that hit the strings, and are attached to thin sticks which we call shanks.
This, in-turn is connected to a wooden hinge “flange”, with a small round felt bushing in it, which connects to the hammer butt “in the upright piano’s case” by inserting a small brass pin.
The flange has two ears which goes over the round hole “the bird’s eye” in the hammer butt.
It has to go in snuggly, but not too tight to cause too much friction.

This is the cause of most sticking keys that I get to.
I can either spray it with a lubricant, or just insert a smaller pin, etc.
You can also resize the bushing.

On the back of the grand piano hammer head, is a tail, which the back check of the key catches.
On the upright hammer, there is a small block, covered with bucksckin which also is caught by the back check in the wippen.
This serves the roll that when you play the key, and don’t let it come up all the way, but play the key again, that the hammer is caught, before it falls back to its original playing position.

The Whippen:
The whippen is the important link between the key and the hamer.
It consists of the following parts:
the jack “to propell the hammer toward the strings”;
the backcheck, “which catches the hammers”;
the bridle wire and bridle strap “in uprights” pull back on the hammer, and also allows the whole mechanism to stay in-check when you take it out of the piano;
the damper spoon “opens and closes the dampers on upright pianos”;
repetition lever “forms as an extra of performance to repeat notes quickly, and to make the jack move faster on grand pianos”.

The 88 keys on your piano “some models have 85”, are all basically made out of pine wood.
When you sit in front of your piano, you only see a third of the length of the keys.
The rest extends toward the back to come in contact with the action of the piano.
The front part is covered with either ivory or plastic.
If your keys still have ivory, then it is divided into three parts:
the front, “facing you”, the heads, and the tails.
The heads are wider than the tails, and the tails tails off to the back of the key.
Keys also have lead in them to add weight where necessary.
Keys have holes in them covered with felt, which match the keypins in your key bed, to keep them all in line.
The capstan can be found on the back of every upright key, and in the middle in a grand piano.
Grand keys are longer than upright keys.
It is the capstan that comes in contact with the whippen.

The dampers’ main job is to mute all sound of the strings after the pedal is released.
There arn’t as many dampers as keys, since the higher treble strings get quite quickly.
The upright damper spoons open and close them. And the back of the grand key lifts up a damper lever, which has a damper wire in it, connected to a damper head with the felt glued on.
The upright is almost the same, but it needs an extra spring, to eep the damper against the strings.

We get three different damper felt:
unichord that fit over one bass string W-shape;
bichord “that fits between two bass strings “V-shaped”;
Trichord that fit between three tennor strings;
flat dampers which are just normal flat dampers, that are used in the tennor and treble area of the strings.

If you’ve read so far, I just want to tell you that I’m proud of you.
Now you know a bit more of a piano’s playing mechanism than the average person on the street.

What is my conclusion?
All these parts are mounted on rails in the action, and screwed tightly.
Over-time they get loose, or worn from use.
Felt get dents in them or get eaten by moths.
Hammers get worn from playing, and so get grooves in them, which we usually file round again, as-new!
We also blow out the action from all dust particles.
If any parts are broken, we will fix it, at an extra cost.
It is necessary to take out the action from the piano to do this kind of service.
I usually ttake it to my workshop, but I have done it in the clients’ home.

Hope this was interesting.


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