I posted about this a week ago. A big thank you to Benjamin Sanchez who posted the solution in another thread.
On a grand action
When the jack would return there was an audible tick. This sound is similar to wood on wood. Like the felt is gone under the hammer butt on an upright. As usual, there is a 4+ mm pile of pressed felt and a spoon.
The pro felt had little to no effect on the sound. I let it dry a few days with no jack spring pressure.
There was a black spot on the stop felt and this was a dusty action so I found a small threaded tap and gently cleaned the dirt off the face of the felt.
Some change in sound but still a wooden tick that resonates
Ben suggested needling the felt with a chopstick voicer. Jurgen sells them. I have a brass one from Joe Goss but it was suggested it is too thick to get in easily. I realized Claudio had given us one as a gift from Fazioli at the all day seminar in Utah a few years back. I chose the most offensive section and stabbed the felts 10 to 20 times. A slight wiggle and lift seemed to help the whole thing plump up. Seemed to be doing it!!!
I jumped up and went in the house without marking where I was. Uh oh. I went down the line of jacks, flipping them.
BINGO!!!, it was so obvious where I had stopped. No tick just a dull thud where I stopped.
A 30 minute fix.
I bent the spring to resemble the shape of a steinway rep spring. No difference in noise.
I removed 2 grams of weight off the hammers. The weight was 10+ grams up to note 48 with 4 leads in the keys. I replaced the flattened knuckles.
Obviously the change in weight will soften the spring.
The combination of proper regulation and fluffing the felt should do the job.
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Keith Roberts
owner
Hathaway Pines CA
209-728-2163
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