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I was having a conversation this past year with a prominent big-city piano technician who says he believes in the value of sorting the hammer shanks by tone - higher pitched shanks in the treble and lower pitch in the bass.

I was sorting through a set of new S&S shanks and contemplating the value of this. I've never bothered to do it before, and I question if its worth the trouble. The recent conversation about WN&G shanks got me thinking about this.

I would assume a higher-pitched shank is stiffer and I could see the possible logic of using them in the upper portion of the scale.

I did go ahead and listen to all the shanks as an exercise and found that the lowest sounding shank was about a perfect fourth lower than the highest pitched shank. However, since S&S side tapers the top section's shanks, the pitch dramatically drops for those shanks. I would gather this because the removal of material on the sides of the shank is lowering the stiffness.

Another interesting thing I observed is that the position of the flange makes a big difference on the pitch of the shank, at least when hitting them on the side. After experimentation, I found I got the clearest tone hitting on the side of the shank on a small anvil and I made sure to keep the flanges in the same position.

If greater stiffness in the high treble is desirable, wouldn't it be better to not taper the sides? Will any difference actually be noticed in the tone of the piano?

I'm curious what others have to say on this subject.

Ryan,
I have not sorted shanks for tone and just cannot see any value in it but I know that lots of tech do this.
However, if I did and there was any real relation of pitch to stiffness, I would install the stiffer shanks in the bass.
Reason being there would be less flex where the hammers are heavier.

Interesting! I can see your point. It would be interesting to take the highest and lowest pitched shanks and try them on adjacent high treble and in the bass and see if there is a discernible difference. It could be a case of what one of my college professors used to say: "A difference that makes no difference, IS no difference."

I sort the shanks after I get a batch just by dropping them on a hard table. Don't sort particularly for any specific part of the keyboard. About 5% them dont get used because they make a dull thud...maybe a crack or something weird going on with the grain alignment or possibly cut closer to the heart wood of the tree.

I also keep a couple dozen cedar shanks I turned on a lathe for some pianos in the top register. Seen this done on some fine quality pianos in Europe. Cedar gets a bit more response on the highest notes.

The reason for sorting shanks is not that it makes much, or indeed, any discernible difference except that occasionally, a very feint wooden additional sound occurs on an odd note or two in the treble. It was more of a freakish occurrence. This is often not heard by many people, even experienced tuners. The point is, it is heard by some piano owners and the conciencious manufacturer had to do something about it.

It was originally cured by thinning the hammer shank, or replacing it.

Since 'in the field' problems are a bit of an embarrassment to a manufacturer, not to mention the expense, it was found that quickly sorting through enough shanks so that the top 15-20 notes had shanks of a higher pitch, this problem was obviated. Thinning the highest shanks does much the same thing, We hear of 'tuning the shanks' with sandpaper. My guess it probably refered to the same problem.

This sound can be still heard occasionally on some pianos, I usually used to hear it on uprights, surprisingly often, to one degree or another once I had learned to hear it.
99% of the time it goes unnoticed or ignored. Some manufacturers or their representatives who can't hear it find it easier to accuse the customer of hearing things that aren't there.

The sorting of shanks by listening to them drop seems to be more of an insurance than anything.

Drummers pick sticks that are the same pitch. Some even have preferred pitches. I can't imagine finding 88 shanks at the same pitch.

How much does the pitch change after the hammers are hung?

'Sounds like a great time-passer on a slow day if the electricity is out and you can't watch golf or cooking shows on TV.

Once you get the hammer shanks sorted, you can sort the grand knuckles by how high they bounce off a table top.

I have sorted upright hammer shanks, but by weight, and not by size. Coincidentally, when I went back and tested the sound, there was a direct correlation between the mass of the shank, and the pitch. If memory serves me (which it may not!) the lighter shanks made a higher sound than the heavier shanks. I found weighing to be more objective than trying to hear the pitch of a dowel.

Emmery, I agree with your use of Cedar and sounding shanks as a way of finding imperfections.

Mention of Cedar also reminds me of broken shanks which, in turn reminds me of grain orientation being important when installing upright shanks or upright style shanks that occur in some older grands.

Dave B,

Good point about the drummers. I just thought of arranging all the shanks in order of pitch throughout the whole piano. I wouldn't dream of doing that (until now)!!!!. It's not nearly that exacting and we might be forgiven for thinking that, with the addition of a hammerhead, butt and flange plus their attendant felt and leather that none of this would make any difference, but it does.

One question raise a thousand more....are higher pitched shanks necessarily stronger than lower pitch ones?

I never bothered to rate them in pitch variance since several variables can be attributed to the difference and you can't always assume its density/strength or size. You get a bag of a couple hundred of them and they could be off of thirty different trees for all you know. It could be variable moisture content also.

If I became that involved in perfection I would likely be taking durometer readings on felt, scanning the soundboard with a SLDV and stopping every 5 miles to check my tire pressure in the car.

A very tiny partial hairline crack in the wood can deaden the resonance and thats primarily what I listen for. I hear'm ring or they thump with a tubby sound. Occasionally if I run the end in a knurling tool and I see the wood fibres raise away,frizzle or cast off a chunk, I'll toss those too. They probably were sitting near a wall in the kiln or dried out a bit too much.

What would be nice is if they put a tiny label on the grain orientation like they do on baseball bats, my eyes go buggy after a while looking at'em.

grain orientation is indeed necessary for vertical shanks, and some dull shanks can be find in a grand shank set sometime (1 or 2 in a Renner set) if left one can have a dull note

The pitching is done for the high treble, then once the heads are glued they are also adjusted so no percussion tone is high pitched than the neighbor, in high treble mostly, but if the shanks have been sorted it can be done farther.

sounding the assembly on a metal blade is easy, action in the piano.

scraping will lower the pitch;

Harder shanks are for the basses, I would say that sounding shanks is done to obtain shanks with similar elasticity, the attack resonance is only heard in the high treble (and it comes from the plate, I have been said)

no grain orientation on vertical shanks is looking for trouble. as a small channel is done on the shank for the glue to escape well it can serve to locate the wood orientation at the same time.

Ryan:

I had some random thoughts on this just recently, but little practical experience.

Steinway makes their shanks by cutting a pre-made plank with one long hammer knuckle, don’t they? So I don’t think they would then sort their hammers according to tone.

As far as reducing the width of the shanks in the treble, this would make them a bit lighter, but I don’t think it will make them much more flexible (bendable) in the direction of the applied force. For instance, when you consider the “modulus of a beam”, a 2x8 joist is much stronger and less flexible than two 2x4s side by side. But I think a thinner shank would have a higher resonant frequency. I suppose that was the thinking behind those cedar shanks in the treble of old uprights. Or perhaps the thinking is to make the weight of the hammer and shank more proportional.

That's what surprised me: The thinner shanks had a much lower tone than the non reduced shanks.

A thinner shank bends more easily, i.e. it is less stiff. Naturally it would have a lower resonance frequency than a stiff shank.

That is how tone bars, like on xylophones, are tuned. Thinner is lower, shorter is higher.

Personally, I'd think rolling them down a shallow incline would yield more usable information that playing them like miniature drum sticks. At least you'd know which ones were reasonably straight.

A dab of moisture on the end will show up the grain orientation.

I agree, Jurgen. So the question remains - what is the purpose of the tapering the sides of the shanks in the high treble? Is it an advantage to have a more flexible shank in this area? Could the flexibility mitigate some of the impact noise in the high treble? It seems counter-intuitive to want more flexibility in that region.

David,

I agree with you, if we are talking about upright hammer shanks. But I'm referring to grand shanks. Rolling is out of the question, and grain orientation is built-in.

Ah ha! In the immortal words of Gilda Radner, "OK, nevermind!"

I find the vertical shanks generally very straight... (Renner) then I bend them with heat smetime

The orientation can be noticed from the sides more easily than from the end of grain, moistening can help, but the small white dots are easily seen.

When scraping with a steel blade a grand shank the resonant frequency go down...

The shank flexibility opens the tone, ... and adbsorb some energy at some point. In some way the shanks could be "voiced", but I know a colleague here that is so extreme in doing so, he cuts the shanks near the beginning of the thin part, with cutters, really extreme. The shanks are so flexible the FFFF is not possible