Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Jack head position on hammer knuckle

Interestingly my new piano, Renner action, was delivered with the hammer knuckles resting exactly at the center of all the jack heads. I know this is wrong- the back edge of the jack head should align with the back edge of the knuckle core. Can anyone imagine a senerio where the Estonia factory would purposely regulate it this way? Could this possibly be the way it should be? Any idea how the action will feel different if I reposition it correctly?

Greetings,

This is the norm for new pianos I have seen. The felt on the jack-stop button has compressed, allowing the jack to move distally under the knuckle. This increases the work, via friction and duration, needed to play through escapement. A new action HAS to play without notes failing, so the beginning position is to favor safety over sensitivity. You may find that those same "dependability at all costs" showroom set-ups usually have springs set too strong for maximum sensitivity. All actions need to be regulated at the six month mark if they are played daily and expected to perform near their original design. If a piano owner has not done this, they are missing a large part of what they spent their money to own.

As the jack is moved proximally, (towards the keyboard), the knuckle friction lessens, the action ratio will change a very small amount, and the less key-stroke is involved in escapement, since the tender will contact earlier. Too far proximally and the jack will skip out from under the knuckle on a hard blow. In between failure and perfect is a small area in which the jack will be escaping early, resulting in loss of power but not skipping. This is hard to detect without a lot of experience and knowing what you are looking for, so I would suggest, if you have to get in there, to adjust the jack so that the distal edge is aligned with the distal edge of the knuckle core. Avoid triangulation errors by observing the jack from 90º, and don't do it if the repetitions are not correct. Don't set the repetitions until you know the spring is correct, and you can't finely set the spring until the dip is correct.

When beginning action adjustments, remember that change often comes in pairs...
Regards,

Many thanks, Ed. We can always count on you for a clear presentation.

Ed, Thanks, you've cleared up a lot of issues. Safety over sensitivity, and dependability at all costs, explains also why my piano came with a overly large letoff and drop. Nothing would kill a sale in a shop faster than a blocked key, while few buyers would notice a slight loss of sensitivity. Felt compression after 6 months of playing explains the rest. I was too tough on dealers not sending their sold pianos out without a finer regulation.

All actions need to be regulated at the six month mark if they are played daily and expected to perform near their original design. If a piano owner has not done this, they are missing a large part of what they spent their money to own. Ed Foote

This seems to be neglected advice for owners of new pianos. It appears to be labor intensive- read expensive, but for those that have spent a considerable amount on their purchase, and appreciate the feel of a well regulated action on a sophisticated instrument it's well worth the expense. The most labor intensive expense would be at the first regulation at 6 months. Subsequent regulations I imagine would be faster minor adjustments.

It is a small minority of people who understand this and actually do it.

Pwg

As with all regulating specifications, be careful of what you "know". You have quoted the "safe" specification. However, depending on a number of factors, moving the jack top slightly forward (ahead of the back of the knuckle molding, ie toward the front of the keys) may result in superior performance.

Excellent post, Ed, but I believe this detail is not correct. Moving the top of the jack forward will cause the jack toe to contact the regulating button later but escapement will happen at the same time because the jack top doesn't need to move as far. In fact changing the position of the jack top either direction doesn't in itself change the moment of letoff. This may be counterintuitive but it's how the action works.

I believe a photo of the situation would be better to evaluate since the OP's description is not absolutely accurately decipherable. That is simply my opinion. I could not, with certainty, determine exactly what he was describing. A photo will make it absolutely clear.

Pwg

Yes, it should have read "later".
Thanks,

It is always great when a simple question leads to some very thoughtful review and solid information!

When you look at the interests of the new piano dealer,...

telling a customer that they need to completely readjust the piano action in a few months is contrary to most sales training. In sales lingo, such truth would be called a "perceived drawback". Would it be more ethical to fully inform a buyer? Yes.

The salesman probably thinks along these lines: Many of his competitors will not share that advice. His take on such disclosure on his part, then, may be considered to be the cutting of one's own jugular.

When doing a restoration proposal, I list the number of post-delivery tunings to be done. Also, there is a notation that the action should be readjusted in [blank] months, depending upon the anticipated usage of the piano. This is akin to the same negative selling described above, but it seems best to put it in.

Greetings,
It doesn't help anyone make a sale to add that the customer will need to spend another $ 1,200 in a few years....

I have never encountered a customer that was told, at point of sale, that the piano would need anything more than "tuning". Some of the professionals understand that all gear needs maintenance, but even they don't know exactly what is needed.

However, there is a class of customer that appreciates this info, and will recognize and trust the truth when they hear it. If the seller is really projecting a sense of honesty because they are being honest, even the un-informed will respond favorably. Bill Garlick hammered the message that a large part of a successful tech's job is educating the customer. I have found that to be true.
Regards,

They don't even seem to get told how often the piano will need tuning to stabilise it in the first couple of years.

And what's sad is that that fear is not even connected with reality. I was a Baldwin dealer for about 10 years or so. I was in a smaller market where most people worked in mills or on farms. It definitely was not an "arts mecca". But I received awards for sales volume and I always told people the truth. The truth about piano quality and the truth about service needs. I didn't sell a piano without a full Dampp Chaser system. And while most Baldwin dealers sold 80% of Baldwin's lower (Howard) line and most of those were spinets, I sold 80% of the upper line (Acrosonic) and most of those were consoles. And I never once used any form of high pressure sales or the popular "three-drop-close".

Of course, my pianos were always in tune and regulated, too. ;-)

There is no excuse for any dealer not to tell the same story the piano technicians do.

Another factor in Ed's $1,200 regulation later cost is that amount becomes far more significant in a $10,000 piano cost compared to a buyer who shelled out $60,000+. I thnk Ed's figure is probably low.

...ok, so perhaps we've strayed a bit off the topic of jack-position-under-the-knuckle, but I'll bite:
May I ask what the "three-drop-close" is a reference to?

Greetings,
That is the mean figure for regulations I see. A C-2, played 6 hours a week in a home, will need all the buttons turned at 5 years. That doesn't take $1,200 worth of time. Most 4-8 year old pianos can be regulated to near new specs in a day. However, if you add in some pinning, maybe hammer shaping, maybe a lot of needles cause it never had none.....

I gave a presentation at the Institute this year on "Three Regulations". It covered my thoughts on different levels of regulation and what really makes a difference is when you have to correct makers' errors, or repin. Then the time goes up considerably with the additional work that has to be done to justify a newly pinned action, (like polishing capstans, pins and springs, shaping hammers, etc.)
Regards,

It is a bit off topic. But the "three drop close" is a sales technique to quote a much higher price and plan on coming down three times to make the customer think they got a good deal. My philosophy was different -- more like the GM's Saturn dealerships: Water's already wrung out of the price, no fake negotiation and your price today is the same as what your high-powered-negotiator neighbor will get next week.

Ah, got it. Thanks! Sounds like the best defense would be to hold out for the fourth price drop

Some years ago there was book: "How to sell your house yourself in three days" (or something pretty close to that). In it, the author stressed the need for FULL DISCLOSURE...letting the prospective buyer(s) know up front and in writing, not just the good points of the property, but also all of its defects, oddities, things that were done wrong and needed to be fixed, etc etc.

Real estate agents were aghast at this advice, as they would NEVER point out bad things about the property for fear it would drop it's value. However, the point was that an honest and realistic buyer will appreciate knowing in advance these details (instead of having to learn them by chance or under adverse conditions) and is actually likely to be willing to pay MORE for the property in exchange for this open honesty on the part of the seller.

It works.

Pwg