22 June 2023, 08:47 PM
NinaThat felt good!
What great feedback! Congratulations.
23 June 2023, 12:14 AM
RealPlayer“That felt good.” I see what you did there…an intentional play on words.
(Felt as a noun.)
25 June 2023, 01:44 AM
piquéquote:
Originally posted by rontuner:
1. Pre-treat hammers by steaming from the top. I use a combination of 70% alcohol and white fabric softener to begin. Dropper onto the top of the hammer and then a small hammer iron across the top. This tends to puff up the surface, including the compacted string grooves. (Then less felt needs to be removed during the next stage)
As this is a Petrof, aren't these hot-pressed typical European hammers that want to be bright? By making them poofy, doesn't it make the tone muffled, even with the sanding that comes after? And didn't you have to wait for this to dry, adding to your time spent on the job?
quote:
2. Shape hammers - One teacher in the past told us to follow the layer of felt to find the shape the hammer 'wants'. Not all felt allows for that with more modern high-heat and pressure created hammers. My goal is to almost, but not completely remove the string grooves.
by shaping do you mean using strips of sandpaper?
quote:
3. Gang-finish the top surface. Using the finer grits with a wider sanding paddle maintains the level of the striking surface to better match the string level. Sanding done with hammers lifted to string level.(usually no work mating hammers to strings)
i am imagining that this step would bring back some sparkle after the use of alcohol/fabric softener.
quote:
5. Sliding action in and out of the piano multiple times to further use the liquid approach in different (specific) areas of the hammer to alter attack, power and sustain. My goal was to 'tone down', or 'darken' the attack without making it 'dead'. That's sometimes a fine line!
oh yeah! don't you find that it sometimes goes too far and you have to put sanding sealer or some other hardener on there to consolidate the felt a bit again? Or would that just overwhelm the felt?
quote:
6. I may have used a single needle in a few hammers that still sounded different from neighboring notes. I still wanted a growl possible in the bass graduating to a warmer middle with some sparkle possible in the top octaves.
(Photo Chris Chris Chernobieff - long post on dissecting the tone of piano hammers on pianoworld. He's done a great service bringing together a lot of the past information on chemical voicing.)
cool! i have somewhere in my collection of voicing tools and implements a hammer that the klavierbaumeister at Grotrian gave me--he marked it up with where to do what very similar to what you've shown here, including the angles for the needles. I've never dared to take it up, especially not after learning about what a steep learning curve it is. But I think I remain more interested in the tech end of pianos than playing them or even the music.
thanks for expanding on the description for me.

25 June 2023, 09:17 AM
rontunerLong learning curve - yup!
The trick for me is to never "go too far" ;-) Which also means that I usually need to do a little more near the end. So I get to "less bright" pretty quickly without going to "muffled"
The hot iron steams out the liquid - the alcohol flashes off quickly. 70% has more effect than 90% - more water, which does the work.
Shaping treble hammers that are perpendicular to the strings, I start with a ping pong paddle covered with two different coarse grits to get most of the shaping done.
The angled hammers I use a plexi paddle with sandpaper glued at the end - that way I can use as a sanding stick or let the paper go free and "shoeshine". Again progressing through finer grits.
My pick for hardener is "big and sexy" hairspray - essentially a water-soluble lacquer. There are lots of other options in use. Didn't have to touch this for the Petrof. Occasionally I will hit the hammer against a wooden plank held up at string height to compact and gently harden the surface for slight changes.
25 June 2023, 07:48 PM
piquéisn't it fun? i mean, i love how every tech i have watched work has their own unique bag of tricks.
25 June 2023, 09:30 PM
rontunerIt's fun when it works according to plan....
When it doesn't, then I get to lean on everything I can remember from all of those other techs that have shared methods!
Nagging in the background is always the question of "am I adjusting what they want changed??" It goes back to trying to learn from the client as much as possible with the language we have.
Honestly, some techs only work with hammers/brands that they know because they have a plan that pretty much works every time. That's not often the case working with existing hammers/pianos found in the home.
27 June 2023, 11:30 AM
piquéi encountered that a lot. "he's a boesendorfer tech! he'll make your piano sound like a boesendorfer!"
