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My Knight K10 has, from C2sharp (did I write this note name correctly?) downwards, hammer heads that are at an angle less than optimum to match these bass strings.

There are several hammers whose edges are only 1mm from touching a higher note's left string.

Is this typical or is its "Langer 80" action a mismatch?

Ian

Perfectly in order as long as the spacing is correctly matched to where the hammers contact the strings. The easiest way to check the spacing is to look at the grooves on the hammer noses .... if they are central the spacing is correct, if not they need adjusting.
Often the spacing appears incorrect when viewed from the top, but unless someone has adjusted them incorrectly in the past the string grooves should confirm otherwise.

There is a compromise to be made here. If the angle is too much then the hammers will touch as they pass each other.

Thanks for your reply. The grooves on my piano are not running off the side of the heads. Perhaps premature in my early learning phase but with the help of Arthur's book I marked the center then gently fine sanded each hammer (towards the tip) before starting and have now completed the 88 note 20 Cent uplift.

When initial tuning is complete I intend to voice the hammers after reading more about the technique.

Ian

Ditto Zeno Wood and I will add that I have never found a good reason to match hammer angle with string angle in bass or lo tenor sections - 6 to 8 degrees max has always worked ok for me.

Zeno,

Thanks for your reply. I had not visualized the hammer movement arc in comparison to hammer "angular width" but I have now!

Ian

Beemer, I am learning this stuff too, for use on my own piano. I, however, will likely do extremely little in the way of voicing, because this is a very fine art, and I think it can be said that one has to be prepared to ruin a few sets of hammers in the learning process, if you are learning on your own. I'm not ready to learn to hang a new set of hammers after ruining a perfectly good set, not to mention that they are the original, tho lightly used, hammers on the piano, and 125 years old.

Bass hammer and whippens flanges are positioned a little apart of the vertical from the strike point for that reason.

Despite the small angular move you cannot have the heads square of the rail and square of the strings at the same time.

The shank axis is also not centered on the flange axis, but this may play a minimal role with the lateral displacement of the head

Cynthia, the fact is that the felt retains not so much tension in time, after the scales of the fiber have fallen due to dry conditions and too much effort. So an old felt can be adapted to the tone possibilities of an old soundboard, but you are right you cannot learn to voice on them, the maximum that can be done is shaping and making the crown less hard.

Deep needling does not stay, nor give a real result. On the contrary the felt will be "dismounted" and power lost. Can only be back a little with impregnation products. That are mostly used in that case to allow a little voicing.
Older felts could be of excellent quality however, and retain some elasticity, to be preserved in that case. No deep needling just cut the extra impact noise.
Filing is just to have a more efficient shape. The zones in the hammer are less tense than the outside, so you can have a cleaner tone but minimal power and dynamics.
On old piano recovering the hammers is often the best choice.

Cynthia,

Good to meet another tuner newbie! When I bought my Knight K10 28 years ago it was after comparing it to a Yamaha upright. At that time I felt that the Yamaha was too bright for my liking so I chose the K10.

Soon after I began to regret my choice as the sound was much "softer" than in the shop. This was because my piano now sat on a heavy wool carpet.

Two weeks ago when I started regulating the action I noticed that the length of the string impression on some strings seemed much more than on other strings obviously through my playing in certain key signatures more than others. My thought was that 'the longer the string impression, the less 'pure' the note will sound'.

So that was when I read about reshaping the hammers and how voicing is carried out. After reshaping with a hammer sandpaper file the sound is significantly brighter but not evenly so across the 88 notes.

After a few more tuning passes I will begin needling the hammer shoulders of some of the brightest notes to see whether I'm competent to continue the process.

I have no intention to tune anyone else's piano so the risk is all mine.

Ian

Do not needle the shoulders they are sustaining the crown.
It is possible to do some sort of deep needing but only if experienced enough. What remain of tone dissipate at the speed of light on old hammers.

Beemer

Have you made sure the strings are all clean and well seated at their bearing/termination points including behind the pressure bar, that all the plate screws are tight enough, and so on?

I've found that all that can bring up some notes and reduce the need for (unnecessary) voicing.

Ian,

I never thought that plate screws would slacken. Some strings do have slight corrosion but appears as discolouration rather than rust. This happened during a phase of keeping marine fish in the same room which I'll not be repeating. None of the double wound copper has discolouration.

Ian

Issac,

Sorry I should not have used the word "shoulder" as I see from Rebitz diagram that this is across the 'loud' section. I do not play loudly so I'll needle deeply in the medium areat that is some time away.

thanks,

Ian

Don"t it have been done yet, probably.


you may harden the top of the hammer but loose power. I don't know the hammers condition or type so I just say do not try to do deep needle them without reason and knowledge .
It does not really happen that old hammers are highly dense in the low shoulders. The too strong tone is not sourced from there.

Beemer, do a search on 'angel shot' voicing. It seems much less dangerous for the hammers.

Hello Mr Oleg,

Thank you for your information; however, I see many things that you write you should NOT do in this situation. For example "Do not deep needle" , "Do not needle the shoulders they are sustaining the crown."

You wrote: On old piano recovering the hammers is often the best choice.
What exactly do you mean here.

Any how I am trying to figure out what you ARE recommending in this situation-

Best regards-

Hello,
Hammer ecovering:

you need to send the old hammers yet mounted on the shank/butt to a shop that take out the old felt and glue new one in a press (often Dolge type presses are used)

That way the mounted felt have new tension, generally well preserved because no real heating.

The difference with modern pressed hammers is the lack of resilience in the heart of the hammer so the FFF nuances are not as concentrated nor as powerful.
The high treble need to be reinforced, but those new recovered are voiced as new ones, less of course.

I said no deep needling as the gain will be nihl , even if some hysterisis can be recovered the tone loose much power at the same time.

The needles say how is the felt anyway, if it does not react we are destroying it a little more.
Only a fast and limited needling near the crown is available.

All the power coming from under is not attainable by needling generally.

For new pianos hammers do not have a so long life in exigent situations. At some point you maintain the voicing at the expense of FFF (if not it does not stay put) . For amateur situation hammers can be kept for decades as long the exigences are not too high in power and projection.

I am more inclined if I use some sort of deep needling to do it once or twice and selecting the part of the head where I do. That way I can take harsh too clear hammers to a moderate round tone in one or jabs

Needling around the crown can be all is necessary, often,then if the power is reduced too much no solution but impregnation.

Needling from under can sometime help as it attain the zones under the crown without disrupting the shoulders.

Needling laterally also, can be located precisely enough, but I believe it does not hold well in time and it sound counterproductive in regard of the layered structure of felt, to me.
Nevertheless, the needling pliers may be a good learning tool as you soften a localized part and hear the result immediately.

The "percussive side" of the head is always to be treated with caution, needled in "angelshoot style or not deep. That part is more solicited when one play strong. When the hammer is needled the other side, the felt tend to densify and gain resiliency on the opposite side, and this brings up dynamics and strengthen the tone at lower levels of playing as well.

Use only one needle and learn to feel where the hard spots are. then unpack with some force the zone. On old hammers you will see there is little hard zone out of the crown (most often)

If the hammers have not been voiced they will have packed a lot.
Why not then doing what should have been done first, but the resiliency tend to not stay put more than 24hrs then lowers a lot and much power have been lost. The noise of the needle going within the felt tells you if some tension remains.

to soften, it is easier to go from top to bottom (no reinforcing under the crown.)

on hammers that have hardened a lot but have no resiliency because the felt is old, needling just one small zone near the crown may be enough. there it should be deep enough to be effective it create a spring near the crown. but that is dangerous, it cuts in the impact noise and lower the frequencies while keeping high partials availeable at stronger forces of playing.

AN over needled old hammer (in shoulders)loose its shape immediately and it cannot be put back by filing, the egg shape always will deform soon.

Regards

Greetings Mr. Oleg.

Thank you very much for your extraordinary detailed information. There is much to be learned here.

How is the durability/longevity of the angel shot method? That is not the 24 h you write of above--or is it?

My recollection is that you also proposed on these pages just month ago (with image) flat-faced pliers for voicing, my impression was you grip the hammer's flat sides. Presumably this is different than the needling pliers mentioned above (not sure what that is too, actually). Is this the case? and if so how does this method (with flat-faced pliers ) fit in with the above.

Many thanks-

Voicing is near the crown, angel thing is fast. Not bad you sure do not needle deep that way.


The flat pliers is used to unpack Hard hammers, as massaging and stretch the fiber, on the round parts, not the sides.

Too old hammers can get a little resiliency back using impregnation and another style of pliers, round inside.

http://www.watanabemusical.com/products/details/index.html?id=jr1337929375

[img:left]http://www.watanabemusical.com/image.php?id=jr1337929375&no=m&pre=thumb[/img]

Not magical but it can help to gain a minimal tone length with some density.

Multi grip pliers allow to have much force and adapt well to the different hammer shapes. the inside is to be filed smooth of course, the teeth suppressed.