Hammers, dampers and unwanted harmonics

[Geoff Sykes]

Just finished reshaping hammers and replacing dampers on an A.B. Chase studio upright from 1900. I understand that pianos from way back then simply do not have the effective damping systems of contemporary pianos. The customer understands this, too. However, when I was done I was left with unexpectedly loud and unaffected by damping overtones. What I see is hammers striking exactly on a point that generates an unwanted overtone, and dampers that are acceptably damping everything but that overtone. Repositioning the dampers higher or lower on the string did not help. It's, obviously, worse in the bass and almost unnoticeable in the high treble. Some needling helped a bit, but not enough. (I'm guessing original hammers, which are extraordinarily dry and brittle. Almost crumbly.) My immediate self-deprecation has kicked in, but I can't think of anything I have done incorrectly. I'm guessing that pianos from that era simply sounded that way to start out with. But I'm not believing myself. I'm open to opinions.

Thanks --

-- Geoff

[Regi Hedahl]

Geoff,

I have improved the damping on these taller uprights considerably by substituting trichord dampers in the tenor. Damping in the bass can be improved with weights. I've heard of using lead sinker weights but have never personally tried it.

Regi Hedahl

[Joseph Garrett]

Geoff,

By 1900, the technology of dampers was equal to today's. (with a few minor exceptions.<G>)

Why not try some Ballistol as has been suggested on the list over the last 2-3 days.<G>

It could be that you "shaped" those hammers to the point, (pun intended), that they are now over striking. That could raise an unwanted harmonic.

 It could be that your damper regulation may be a bit wanting and there is one that is letting you know it.<G>

Or, you followed the pattern of the original damper configuration and it was not quite right. Did the piano have this issue before you did your work? Does it have tri-chord dampers at the break? Are they sufficiently long enough to do the job. (trick: cut the top diagonally upwards. It will conform to the hammer, but not interfere.)

There are some pianos that are extremely lively that are next to impossible to shut down to modern standards. A lot of times it can be a soundboard/scale/original set up issue. Old stings do strange things as well.
My first guess would be a bass string that is not quite shutting down. Second guess is not enough energy absorbing mass some where. Try adding fishing weights, (split shot), to the bass damper wires. Easy to install. A few at a time with tests as you go.

Key factor: sufficient mass to absorb the energy! (of course that is assuming good regulation and felt.<G>)

Del had this issue on his pianos. The piano was so lively that he used brass damper heads, in the bass to shut it down sufficiently.<G>

Best,

joe

Captain of the Tool Police
Squares R I
gpianoworks.com

[Douglas Gregg]

The fact that the hammers are dry and hard makes me think that they
must be very bright as well. I would certainly get a 6 oz. can of
Ballistol spray and use most or all of it on the hammer set using
proportionally more on the bass, of course. More resilience in the
hammers may significantly reduce the unwanted noise. Depending on the
state of the hammers then, perhaps replace them with Wieckert wool
Ronsen hammers that are quite soft. You can voice them up if you find
them too soft but they are probably the most appropriate for that
piano's age.Just my $.02.

Doug Gregg

[Joseph Garrett]

Doug,
Of the four different offerings of felt types from Ronsen, I would not consider Wickert felt to be "soft". The Bacon? Yes.<G> As for the appropriate felt for that piano, I suspect the Wickert would be the closest. <G> Just my take on it.
I agree with the replacement as a possible solution, but suspect it is not the hammers, but rather the dampers and damper system/design.
Another take on it. I outlined the many possibilities in hopes that the answer would be found with careful exploration.<G>
Best,
joe

Captain of the Tool Police
Squares R I
gpianoworks.com

[Douglas Gregg]

Not much can be done with the damper design, and the dampers have
already been replaced. Unless you want to re-engineer the piano.

We have an old upright George Steck with a sostenuto where our church
is now meeting after the fire. It was pretty raucous. After the
Ballistol treatment of the hammers, it toned down a lot without any
ringing or harmonics coming through at normal level of playing,but
when played hard, it still comes through a bit. It sounds pretty good
when played moderately.

Doug Gregg

[Al Guecia/Allied PianoCraft]

Joe, I agree and have a follow up question. Would you say the Weickert is firmer than Wurzen AA?

Al -

High Point, NC

[Geoff Sykes]

On Friday, June 19, 2015 at 8:17:08 PM UTC-7, Joseph Garrett wrote:

It could be that you "shaped" those hammers to the point, (pun intended), that they are now over striking. That could raise an unwanted harmonic.

The hammers were deeply grooved so I'm guessing that those unwanted harmonics were not there. Along with a lot of other more desirable tones. I have no idea when, or even if, the hammers had ever been filed before. The top treble notes still had felt even when I was done. But, the possibility of over striking is indeed a possibility. Follow-up question: Do you think slightly flattening the hammers at the strike point could help?

 

 It could be that your damper regulation may be a bit wanting and there is one that is letting you know it.<G>

Or, you followed the pattern of the original damper configuration and it was not quite right. Did the piano have this issue before you did your work? Does it have tri-chord dampers at the break? Are they sufficiently long enough to do the job. (trick: cut the top diagonally upwards. It will conform to the hammer, but not interfere.)

Again, hard to tell if those overtones were there before. The old dampers were buzzing and rattling so loudly that I would have had difficulty hearing them even if they were present. Dampers are pressing against the strings sufficiently. If I press on them hard enough I can get the string to quiet a bit faster but that does nothing for the harmonic that I am hearing. No tri-chord dampers. New dampers are maybe 2mm shorter than originals and were installed right in the middle of where the old ones were. Moving them up or down does not help. Again, to my ears, it sounds like the dampers are touching at a null point for the harmonic I am hearing. 

 

There are some pianos that are extremely lively that are next to impossible to shut down to modern standards. A lot of times it can be a soundboard/scale/original set up issue. Old stings do strange things as well.

I'm used to older pianos having a slower damping effect than newer pianos. I've been taught that that is normal. That normal damping is happening quite well, except for that one harmonic that is not damping. Like I said, that ringing is most prominent in the bass and gets progressively less as I go up. It's not a single string that is sympathetically ringing, the harmonic goes up along with the note being played. 

With the valuable feedback I have received here, I'm going to guess that with reshaping, the hammers are now over striking onto a part of the string that is activating that harmonic. A place they were never intended to strike. I'm also guessing that the dampers were efficient when the hammers were striking in the correct place, but they, too, were never supposed to have to deal with that harmonic. 

If there is fallacy in this thinking, please, someone, point it out to me. 

[Geoff Sykes]

Why not try some Ballistol as has been suggested on the list over the last 2-3 days.<G>

I just may do that. I tried needling the most offensive note and it seemed to help. Perhaps a Ballistol treatment is in order. Considering the age and condition of the instrument it's certainly not going to hurt. But is does raise a question: 

Not that long ago there was a discussion here about using oils like WD40 and the like on pianos, and how destructive that practice could be. The name Donald Rokos was brought up as an example of just how destructive using oils and other CLP's can potentially be. Please explain how Ballistol falls into this discussion and why it is apparently OK.

Thanks --

-- GS

[Douglas Gregg]

Ballistol vs WD40
They are not at all the same. WD stands for water Displacing
I understand it was first used on airport runways
Ballistol is a water miscible oil. That is quite rare among oils. I
only know of one other.
Ballistol was developed for use on guns and holsters in WWI
WD-40 evaporates. Ballistol does not.
Ballistol is recommended for use on metal, wood, felt and leather.
Wd-40 is recommended metal.Will keep clay from sticking on shovels and
will remove lipstick from towels. No mention of felt or leather or
wood.
Ballistol has been used for more than 100 years. It is used widely on
rare guns on wood, metal and leather and felt.
Ballistol has a basic pH and inhibits mold and bacterial growth and is
biodegradable .
There is no comparison other than they are both oils-sort of- but are
very different.

Brake fluid is not used as motor oil. There is a difference there too.

Doug Gregg

[Joseph Garrett]

I have been told that it is. I have not, as yet, found a need to use them.<G> I really like the Wurzen and the Bacon for the types of pianos that I generally am working on. I am not above using Renner hammers if the piano demands them. <G>

Best,

Joe

-----Original Message-----
From: Al Guecia/Allied PianoCraft
Sent: Jun 20, 2015 1:54 PM
To: Pianotech Google
Subject: Re: [pianotech] Hammers, dampers and unwanted harmonics

[Joseph Garrett]

For one thing you are not getting it around the tuning pins. All solvents, elixirs, fluids, magic potions and such should always be used with intelligence and forethought, imo. The WD-40 discussion was in regards to applying it where it should never be and w/o regard to any consequences.

Case in point, Wurlitzer used pure silicone diluted in Naptha to take care of the atrocious flange pinning that existed. It worked. Why? Because it was only used on the action. Did it creep? You betcha. Did it attract dust? Yup! However those suckers did play. (albeit not with much musicality.<G>)

Best,

Joe

-----Original Message-----
From: Geoff Sykes
Sent: Jun 20, 2015 3:08 PM
To: pian...@googlegroups.com
Cc: joega...@earthlink.net
Subject: Re: [pianotech] Hammers, dampers and unwanted harmonics

Why not try some Ballistol as has been suggested on the list over the last 2-3 days.<G>

I just may do that. I tried needling the most offensive note and it seemed to help. Perhaps a Ballistol treatment is in order. Considering the age and condition of the instrument it's certainly not going to hurt. But is does raise a question: 

Not that long ago there was a discussion here about using oils like WD40 and the like on pianos, and how destructive that practice could be. The name Donald Rokos was brought up as an example of just how destructive using oils and other CLP's can potentially be. Please explain how Ballistol falls into this discussion and why it is apparently OK.

Thanks --

-- GS

[Jurgen G]

It is interesting how quickly this thread morphed from damper problems to voicing hammers. Have you tried to take the hammer out of the equation? Raise a damper, strum the strings of a unison and release the damper.  Same result?  then you know messing with the hammers will not help.

Replacing damper felt is not an absolute.  There is damper felt, and  then there is damper felt.  Some has better or worse damping characteristics than others.  Some is plain awful.  You usually get what you pay for.
Trichords in the low tenor have been mentioned - a good idea.
Then there is spring tension vs. damper head mass.

Find out more about all this at my upcoming damper troubleshooting class in Denver.

[Joseph Garrett]

All discussed before it "morphed".<G> Blatant with the commercial there dude.<G> Have fun.

Best,

Joe

-----Original Message-----
From: Jurgen G
Sent: Jun 22, 2015 10:36 PM
To: pian...@googlegroups.com