Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Tight Key ??

On my piano, I can physically raise the piano key by roughly 1/2 cm. But in that short travel, there is a considerable tightness. Once its up, it will not return to its original position. I need to push it back down to return to its normal state.

Is this normal?

Or is this a sign of humidity issues?

Aside from this, there is no apparent sticky key issues when the piano is played.

Thanks for your time everyone.

You are raising the key above its normal height? That is not a good thing to do. It will bind on the balance rail pin, which can damage the key while causing the effect you are seeing.

Most keysets have something that keeps the keys from being lifted too far, but not all of them do.

hi bdb. i am in no way forcing the key above its height (at least i don't think 1/2 cm is forcing it). but my point is, even before it reaches that height, there is a fair resistance already.

i was under the impression that the keys can freely move up (to whatever height it will allow) and drop down when i release it.

is my understanding correct?

No.

thats great news. i was concerned for nothing. thank you !

Stop lifting your keys! If it plays ok when you use it normally, you don't need to worry, but if you keep doing what you are doing, you might damage something that is expensive to repair.

got it! thank you.

??? Why do you both say that? A piano is not that fragile!

There is no harm in to gently lifting the key to see if it falls back to the balance rail on its own accord.



Correct! This is the way we look for a too tight balance rail hole in the bottom of the key.

However, if the key works correctly there is no need to ease the hole. And if required you need a special tool to do that.

I agree with Rafael. We always lift the keys way beyond that hieght to remove them completely from the key bed to do different things like clean under the keys, add or remove punchings, etc. It does not damage the key.

Also, we lift the key to check for tightness in the balance hole, balance hole bushing, and front rail bushing.

If the key sticks close to the bottom of the key travel above rest, like you are describing, it could be a tight balance rail hole, or a front rail hole, or a balance rail hole, or any combination.

Tight keys can cause slow return of the key, and poor repetition, and sometimes the key will not completely return to its rest position and the jack will not reset, causing the note not to play.

However, I saw a video demonstration by the Kawai head technician where the tightness of the balance rail hole actually help repetition on fast passages because it reduced the jumpiness of the key on return.

Ask your piano technician if it's a problem.

Of course, you are right - a piano is not that fragile, but there is a difference between a technician lifting a key and somebody far less knowledgable doing it. I was suggesting he stop doing it because I wasn't sure he would be doing it in a careful enough way. The way I see it, if somebody doesn't know what's normal for a key, they might also not know what is safe manipulation of the key. I was just playing it safe for his own good.

Lifting the keys can cause the balance rail holes to elongate. There is binding happening. That is why there is resistance as they are lifted.

When we lift keys, we lift as straight up as possible. If you are lifting from the front of the key, you are lifting so the key is tilted. If it binds, we make adjustments. You cannot do that lifting from the front of the key.

As I said the piano is not that fragile, if you do it carefully, there is no damage.

Arthur Reblitz, The Randy Potter School, etc. suggest lifting from the front of the key to check if the balance rail hole is too tight.

And it is this very way I do it, without damaging the keys and without enlarging the balance rail hole.

If your keys are "falling" free when lifted 2-4 mm that is all good.(they even can be slow)

possibly they are a little tight now or the pins are not as smooth they could; anyway the "ideal" key tightness when it looks as "aspired" on the pin when raised 5 mm is something obtained in good moisture conditions at the factory or shop.
If yours are permanently above , it may be necessary to regulate the keys again, but most often a simple cleaning of the pins is enough.

If some oil have been used on the pins (it happened on brass pins) , in time it get soap -ish and brake the pin.

If cork grease was use to avoid corrosion on steel pins, it also may slow a little the pin.

In very dry conditions, the woo will retract on the pin and brake it.
In very humid conditions, the wood will swell an the hole will globally be enlarged (ovalised) while at the same time the key is slow because the woo just near the hole is also enlarged (and the cloth of the bushing swells).

Depending if the balance pins are straight or slanted the "aspiration" on the pins will not be the same.

To me matters that the back of the key cannot be raised, but the front can be a little.

To have the key going down by itself it is allowed to help it a little.

Yes, no abuse there, but on upright the key is forcing a little to get out, ; as long it is not excessive that is OK.

Opening the hole by massaging the wood must be located where it is necessary (not both sides often) .

Too much can be closed by moistening or massaging.
Only with new keys a rat file (modified) can be used to file inside the hole, here also where it is necessary , depending of the spread of the key, the contact zone is at the left or at the right. This is necessary with the conical inner keys (Steinways, some other) with a flat inside the hole it is less good an less easy to manage precisely.

Above 2.5 mm thickness, the key "shoe" is too thick and will retain the key from rising at the front much. particularly small length keys - if the keys are 200 mm long it is better to get the action out to work on the balance.

Too thick "shoes" may bend the bridge pin visibly, a special too is use to thin the inside then.

I think that depends of the balance rail an keybed geometry. WIth theys that level at mi blow, the pin can be straight vertical, an your comment apply +-.

More often the pins are bend toward the action and you can lift the front to check the balance hole. (not up to binding but 0.5 cm is not so extreme, just a little too high/useless for that control)

There are lots of things that depend on other things. One of the most important is tailor an answer to the person asking the question. Whether it is possible to lift a key without damaging it is not as important as knowing that it is possible to damage it by lifting it, particularly when speaking to someone who does not need to do it at all.

You love saying people what to do and what not.

I prefer to say what I do and let others decide on what they want to do.

Who are you to tell people what to do?

Let's just breathe and think a little bit. BDB has suggested a good answer to a person not technically trained to care for his piano, and he has given a rationale for that answer. That is not the same question as "Is there ever a reason for lifting a key, and if so what is the technique and purpose?" That discussion is not a useful one to have in front of most piano customers, particularly at a distance from their music rooms so that one cannot demonstrate one's technical point and watch to see if one's explanation is clear.

ok so i went to a local piano shop with the sole objective of lifting a brand new key (gently without any force).

here's the video i took (only 4 seconds)... as you can see, i can lift it up approx 1/2cm with no force and it drops gently back down upon release. this was a Baldwin upright btw.

http://youtu.be/kn7l3Q46yPU



this is what i am trying to do at home with my piano. i cannot get this lift/release/drop motion because of tightness.

anyway, like i mentioned, it is not yet a problem but something i need to address probably down the line.

thanks all for your replies.