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Thanks! Yes, I understand in a piano that is the protocol.

I just wondered about the picture posted above on the hammer out of the piano. It looks like the hammer was sprayed from the side above the wood core to see if the 1-1-1 would penetrate the felt already lacquered?

Or, was that really sprayed only on the shoulders and then viewed from the side to see the penetration deep into the felt??

Ron Koval

Ron,

In the picture the hammer is an old one that was laying around from a past rebuild. I don't know its voicing history. But the hammer sounded and felt just like an over lacquered hammer. Hard as a rock. I used the 1-1-1 in a hypo oiler and applied just enough for it wick up from the staple area to the 10-2 position.

Had the effect of opening up the hammer.

-chris

Thanks for the clarification - I was looking at the yellow color near the core as what was added, but it sounds like it is the lighter color coming up from the staple area that you were demonstrating!

Now it makes sense...

Ron Koval

I came up with a new diagram of the hammer. Slightly different than others i have seen. But based on my experience with the chemical voicing seems to be very practical.

Work from the bottom up. Adjust sustain first until it tapers off smoothly. Then adjust the loudness until all hammers are even. Then finish off with the impact to your liking.

Easy! I have come to the conclusion others just made it overly complicated.


-chris

Could you explain the step 'loudness' in detail?

Using the Mrs. as a guinea pig. I instructed her to use the B-72 as hairspray ( shes use to my crazy experiments). Seems like the 1Tbls- 40oz of alcohol is too weak. It doesn't hold like the Big Sexy does. So i'm making a stronger Batch. Once i get this right, the Mrs said she will no longer by hairspray as making it is pennies on he dollar. What a trooper!!

-chris

Hairspray experiment inconclusive.
Apparently, it behaves differently on your hair than it does on a piano hammer. I believe the plastic used in Hairspray is hard and brittle. Great for hair but not so good for tone. That's why you get pings with lacquer or keytop material. B-72 remains flexible so less tendency to ping. Great stuff.

Update on formulations and applications. No longer using the 50/50. Now using a 1 to 2 softener, 1 to 2 B-72, still using the 1-1-1. Now added a 2 oz spray bottles for spot voicing on single hammer. And a hypo for voicing in the volume section. For adjusting volume its better to voice from the side and avoid influencing the impact section.

The experiments continue.

-chris

Instructions for using dissolved keytop material is not very specific, as are most instructions for piano work. The material has varied over the years. My thought was that one should use the material that was first used, which is celluloid, if you want the results the "old-timers" used. Celluloid is much softer than most keytop material used now, and that seems like a good thing.

Also, application should be followed with careful filing. That takes off the top layer, which might have little irregularities in it. What is underneath has been filtered by the top layer.

Hi Chris, thanks for the update. Let me break it down to see if I understand all the steps correctly:

• Spray shoulders with 1:1:1 solution of fabric softener, alcohol, and water
• Spray crowns with 1:2 solution of acetone and B72 pellets
• Spot voice individual hammers shoulders with more 1:1:1 if needed
• Use hypo bottle to apply 1:2 to the shoulders at about 11:00 and 1:00 to increase power
• Spray more 1:2 or brush away excess 1:2 at the crowns as needed to achieve desired tone

Does that seem right?

The 1:1:1 is for extremely hard hammers or excessively lacquered hammers. So far I have only needed it for the sustain area.
The 1:2 Softener, and the 1:2 B-72 are great counterparts.

Working in the volume section I am preferring side voicing as i can get more juice in there before it wicks to the color area. When adjusting the volume i want to avoid the color area. Also, I am preferring to use a hypo for the sustain area. Once Sustain and volume are built and even, i then use the spraying for the color section using the 1:2's.

I do not use acetone. Yes it melts the B-72 quicker, but I am ok with just melting with alcohol even if it takes a few days. Saves me from having to buy another chemical.

On new hammers, it can all be done with spraying to focus on evenness from the beginning of the procedure as Todd showed. So i suppose all of us will develop their own way of doing things. I had to add the other techniques because of working on old hammers. I was delightfully surprised that Todds system brings back to life dead hammers. Made this Steinway M i'm working on sound new again.

Sounds like your doing well with it too.

And yes, I have modified the hammer diagram too after chatting with other fellow Techs..
-chris

Thanks for the clarifications Chris. So I got my bottle of Big Sexy today and lightly sprayed the crowns. I did not like the slight metallic zing it gave everything. I didn't brush the crowns with a wire brush like Todd did in the video. Was that to get rid of the zing? Instead, I lightly gang sanded the hammers with 800 grit and that took most of it away. I think in the future I won't be spraying anything on the crowns and instead just treat the volume section.

As you say, however, we will all develop our own best methods. Unfortunately I only have my one piano do do all the experiments on for now. My wife is threatening to report me for piano molestation.

But when do you work on the 'volume' or 'loudness' area? When it is too loud? When it is too silent? When the loud tones are too heavy?... I don't really understad this area.

Notice that I am working from the bottom up.
You work the volume area after you build sustain. How loud or soft you want the piano is up to you or your client. More important is evenness from hammer to hammer. Too loud would be sitting at the keyboard and one note is giving out so much energy than the others, that it goes right into your ears. In that situation I would apply 1:2 softener to tone it down to match a neighbor hammer that I like. Always good to have hammers that you like and match others to it. It may take one application, or it may take a couple. It depends on the hammers.

Hope that helps.

-chris

Not that I necessarily agree with that diagram of the piano hammer, even with it, I am not clear on which areas should be harder and which should be softer.

I voice according to what I hear and make the changes the hammer is indicating. With the chemicals i am using and the diagram as a mental picture, i have been successful getting the hammers sounding very good.

First listen to sustain. If it drops off in a wave pattern. The shoulders are too hard. Soften. Once all of the hammers sustain nicely move to adjust volume.

Second Volume. If it sound dull, thumpy, lacking power etc. apply B-72 to the volume area. If the volume area has too much energy use softener.

Last adjust the impact sound. Emery just mentioned the hammers had too much ping after one application of big and sexy. Try a pass of 1:2 softener solution. If you then go too soft, I would sand with 1500. 1500 really cleans up a hammers appearance and tone. If you want to just remove the ping with a sugar coating needle thats okay too.

-chris

BDB,
Lets see your preferred hammer voicing diagram that you like.

-chris

I can't really relate to those approximations with a wide range of unknowns.

Is there any representative concert grand with a recording of uncompressed audio quality that you can present as "That's the way a concert grand should sound like."?

I do not think of voicing visually, but I have some ideas that seem to work. As I said, the important thing is the way the string is excited. The shape of the wire when the hammer leaves it is what shapes the tone of the note.

So the first thing is that the hammer needs to be shaped properly, with a nice round shape at the top.

I find that clarity of tone comes from a good definition of that top. A fuzzy top gives a fuzzy tone. If the hammer is too soft, it is mostly at the tip of hammer. Hardening should be near the surface. However, the surface needs enough give that the roundness is not compromised by tiny hard spots on it.

Strength of tone comes from getting the hammer to stay on the string long enough to transfer the maximum amount of energy to the string. This varies widely across the range of the piano, according to the frequency of the notes. The lowest note vibrates about 27 times a second, while the highest note is over 4000. So the #1 hammer should be on the string over 100 times longer than #88. But even note 88 needs some softness. Otherwise why have felt on it at all! Deep needling (or possibly other softening) gives strength.

Sustain comes from the initial waveform and how it holds up as the note decays.

Chris-

Is there only one video of the visit? I am interested to see more about this process of Todd's.

Second part his here: https://www.brighteon.com/78153c40-e66f-4130-a1ba-a41b946d9fa7