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first, to add further informations...

the piano is yamaha c3, bushing cloth from renner germany(i suppose it is of high quality?),and the room humidity/temperature is well-controlled all year round(thus no need for pre compensating for humidity expansion).
keypins polished before rebushing.
and, no, i am not an engineer, a sirious pianist.

yes, now the keys feel "better" that's for sure.
before rebushing, cloths were quite worn,dented, if not totally worn out, so thats no wonder(that keys now feel better).
but the thing is, i wanted my bushings starting out close to ideal as possible, and having read mr boone's book
several times, i supposed his regulation guideline to be reliable(to be ideal).

i told him about this beforehand, yet he had done things the way i described in the first post. plus he regulated about an octave and a half of both extreams of keyboard's bushings looser than the rest, because , he says, they wear slower than the rest(center).
i thought this meant that he thought those looser ones are the norm.
so "is there anything wrong with keys that moves side ways barely visible?"
"does anyone have any objections to boone's recommendations?"

to be continued..

what thickness are the cloths ? they are somewhat thick for Yamahas. 1.35 if memory serves. Nikke cloth, from Japan , is very good.

the side play should not be noticed really.

too much play at the balance is enough to give a less good impression, because the balance is important for the equilibrium of the hand/fingers.
If you have some "baby foot motion" really perceived, there is too much play.

depending of the springiness of the cloth more or less side play allowed. the Japanese cloth is more springy, German cloth more firm.

using too much glue can tighten the cloth and make it thinner.

ungluing the original cloth, glued with PVA glue, is not so easy. an option is to cut in the glue joint. if moisture is used a lot is necessary and as the wood is soft it is too easy to take out some wood with the old cloth.

regulating the sideplay before everything is well dry (a few days depending of the weather) is also giving too much play.

you may check the play at rest and with the key bottoming. The Yamaha tool open more the aperture tan the bottom, making a different play in the 2 positions.

Pliers are better.

As it is a soft wood the mortise can be closed by tapping on the wood.

There should be a tiny amount of sideways play when the key is at the bottom of its travel. The amount of play should be felt usings the lightest of sideways presure, not yanking it from side to side. Remember these are guide pins, and are not meant to increase friction having the pins in constant contact with the bushing cloth.

1.3mm. 1.35mm is the pre-cut one . he used the wide sheet of cloth that one has to tear by hands.

by the way, how do you check the proper fit of the balance bushings? is there any way of checking them exclusively, so one knows if its balanse or front thats not right?

lol what the heck is "baby foot motion"?

Greetings
I check the balance rail bushing by lightly touch the front of the key and watching the back check. If the backcheck will not sway from side to side while I rub sideways on the key top, the bushing is too tight. A light touch, and an almost imperceptible back and forth at the check will tell me what I need to know.
I have never heard of leaving different parts of the keyboard bushing looser in expectation of wear. This guy sounds like a hot-air artist...
Regards,

i am very glad that now i am getting informations from slightly different angles.

especialy mr foote, i always have enjoyed reading your insightfull, logical, educational posts here and ptg archives for quite a long time.

and marty, you seemed to be reading my mind!
my yamaha might lack depth in tone, but i just want to bring
the action to the optimum condition, at least , for a while.

nice tip, Ed,

You also can insert a 0.2 mm blade on the side of the pin and feel how it is tight.

IF 0.05 mm miss on the cloth , that makes 0.1 mm for one mortise, enough to feel something a little sloopy (not much, but enough to be perceived).

But bushing cloth thickness is not as precise, and will depend on air moisture somewhat I had 1.30 that was measured at 1.25 and 1.35 that measured 1.4 (when measured with the good tool)

Pierrot, sorry, "baby foot" is a French name for :

What count is not some theoretical measure , even if the usual numbers are good, but what you perceive under the fingers.

If the keys where worn, the backchecks may be less efficient today ( alittle worn out) , but also the hammer flanges are probably very loose, so as long as the keyboard is stable under the fingers all is well, you will not have further "straightening" of the touch without other options, pinning, correction of worn leathers/cloths, good damper timing.

If you keys have "pulley" (front to back) this is enough to loose some of the benefit of new bushing cloths.

Can be closed somewhat by moistening the wood with 70% alcohol.

Yamaha keys are very accurately made. There is no reason your bushings shouldn't be perfect.

Find a new Yamaha grand and feel the keys. Your keys should feel the same.

mmmmmm, i would love to listen to further discussion two of you would have about this...

yes, i played a new c3 several years ago and keys felt pleasingly tight(no heavy feel).
i had that feel in my mind when i dicided to rebush keys.

I can only express subjective feelings of some professional pianists, who believe that a keys of any grand piano " to drive worse (tight) in the winter time" on the territory of the former USSR. It may be cause dry winter air which reduces the bush hole and we find in a fall of a friction here. A cloth as close to the pin. For a professional pianist is better when it is a key tighter

Greetings,
That is a readily available standard, and if you just had someone rebush your keys, they should feel like that. When reasons start piling up for it not, (a store in Japan does it this way), and trying to explain why some are looser on the ends, I think you should ask the job be done over, to Yamaha specifications. It is a simple matter to do this with the right cauls and cloth.
Regards,

Greetings,
My point is that after the bushing felt is no longer in contact with the pins, there is nothing to be gained by adding looseness. Inre the friction being there unless one can see the key move, my action balancing doesn't support that. I can feel movement in a key that exhibits no more friction in my BW measurements than one that I can see move. Some brands require more clearance, simply because of the number of front pins that had to be bent to space the keys, but Yamaha isn't one of those. ( I have installed two new sets of Yamaha keys and neither of them required more than one or two pins to be slightly moved to space).

When setting up a piano for heavy use, I don't want any more looseness than I have to. Caul size and glue viscosity are also important for the durability of these sets, too. I use overly thick cloth and VS-Profelt to size them to the pin. This is the only procedure that gives anywhere near acceptable longevity in the practice rooms. The older key bushing cloth was far more durable than what is being sold today, and the bushing jobs simply don't last anywhere near as long.
Regards,

Even if it's slightly OT, I'd like to ask a supplementary question about replacing the whippen cushion felt above the capstan.

Is advisable to replace it at the same time as rebushing the key, if not already done?

I recall Isaac saying this can do wonders for the touch.

when an action have played a lot there is some coherence in wear.

Correcting the keys is the most advantageous way to make a better touch, but the wear and looseness of the rest of the action is yet perceived.

Hello Mr. Oleg, I was interested about this for the purpose of reducing side-to-side motion, as described in the original post question.

- Is the alcohol to better carry 30% water deeper into wood?
- Exactly where and how would you be applying this fluid.
- In what doses(volumes) would you apply it before trying its effect (as to not over tighten the wood around the pin)?; how do you get it just right?
- Is there any danger of this fluid interacting with the bonding of the existing bushing/felt to weaken its adhesion?

Best regards-

PS. No one has confessed or supported turning pins. Here is a direct quote from a tech who has worked on my piano in the past; excerpt from an email of his to me:
"The side to side play can also be eliminated by a technician by easily swelling the key bushing, or turning the oblong key pin in the front of the key. This is also something that should only take a few moments for a technician to take care of. " ... and... "As far as the side to side motion goes, you WANT side to side motion."

I would not use alcohol as it can be used to unglue the bushings, and it also shrink the cloth.

turning the pins is used as a fine tuning of the play, eventually, only when the side play is basically good and even and discrepancies are noticed.

As a temporary measure too before re bushing, but it may never allow the cloth touch the edge of the pin, so the range of correction is limited.

What I never do now is to bend the balance pins to correct slanted keys (due to bushing wear). It simply add too much work to be undone later, and I do not like tapping too much the balance pins, with time they can loose their firmness in the wood, better leave them alone, they have been bend when the keyboard was installed, only with light key warping I bend the balance pin).

The moistening of the hole close the wood that can be uncompressed. the results are more or less long term depending of what other work is done and the condition of the wood.

Traditional repair for pulley is to shave a shim with a small V shaped wood chisel, and make a similar cut at the back of the hole. Glue that "boat shape" and adjust the hole .

I have buy a specific tool that allow to cut a round aperture where a new round key shoe is glued. Works fine with 90° holes, way less when the hole is inclined. the quality of the shoe is also to be tested.
I prefer the boat shape.

Thank you for your instructional comments, Mr. Oleg.

Best regards-

you can tap the wood (not too strong) to close the mortise a hair.

not all wood, easy with pine, much less with harder woods.

New pins are luxury on any keyboard, particularely the balance pins. changing them if the plating is lost give really smoothness and eveness.

And the new ones may be a hair stronger (I doubt it is voluntarily but it happens than the pins I buy have <1 tenths of mm more than the original) , which helps with the balance hole (not with the mortise if you did not think about previously).

reproducing the "L shape" of the bushing cloth in the capsule is also important when changing the cloth. make a firmer hold, a precise dimension and less friction. - one hour more than without the recess, but many do not reproduce the original design)