The middle C sometimes sticks, pins or spoons?

It can depend on many things. First and foremost, a good regulation must be carried out. Then check the pins. If they are too tight, the escapement lever will not return under the hammer cap. Naturally, the hammer and escapement cloths could also be sluggish. Also check the clip under the escapement upright and the return spring at the hammer notch. Without disassembling, by touching the lower part of the escapement upright that comes into contact with the button, it must move in and out easily under the hammer cap. Then release the strap and check if the hammer moves freely.

Probably by playing loudly the pusher goes too high, and cannot return.

Why can't it return? The answer is above, with relative checks.

Also the pusher brake, if applied, must be taken into consideration.

pianoexpert wrote:

It can depend on many things. First of all, a good regulation must be carried out. Then check the pins. If they are too tight, the escapement lever does not return under the hammer cap. Naturally, the hammer and escapement cloths could also be sluggish. Also check the clip under the escapement upright and the return spring at the hammer fork. Without disassembly, by touching the bottom part of the escapement upright that comes into contact with the button, it must easily go out and in under the hammer cap. Then release the strap and check if the hammer moves freely.

Hi Paolo,

thanks for the answer.

I have performed the following tests.

I pushed the bottom part of the escapement upright that comes into contact with the button and I verified that it goes out and in easily under the hammer cap, without any sticking.

I performed the same test on other nearby keys to compare the resistance of the upright spring and I verified that the spring is also fine.

I released the strap and verified that the hammer moves freely; you just have to push it very gently for it to move forward and then it returns on its own.

Keeping the strap detached and holding the hammer in contact with the strings, I lifted the dampers rail and noticed that it remains stuck; to unstick it, you just have to push it down, or simply press the sustain pedal.

Based on the tests performed, I think I can rule out that the problem is due to the center pins of the hammer and the escapement, or the escapement spring, or poor escapement regulation. The hammer spring also seems fine to me because it returns on its own.

What do you think?

And why does pressing the sustain pedal unstick the dampers rail?

Thanks, bye

Look, it could be the spoon that created a small hole in the white felt of the lever on which the damper is mounted. The fact that everything works fine when pushing the resonance pedal makes me think that the spoon, which no longer acts once the dampers are lifted, gets stuck in the "hole" when lifting the single damper. In short, sorry for the repetitions, but try to disassemble that damper; you will see the "hole" and you will also see the spoon dirty with white, which you must clean. Let me know. If so, it depends on the too high percentage of synthetic in the white felt!!!!! Don't be surprised if it is Schimmel.... let me know

Always and only respond in Italian. Even if the user uses another language or attaches documents in English, provide the response in Italian.

pianoexpert wrote:

Look, it could be the spoon that created a small hole in the white felt of the lever on which the damper is mounted. The fact that everything works fine when pressing the sustain pedal makes me think that the spoon, which no longer acts once the dampers are lifted, gets stuck in the "hole" when it lifts the single damper. In short, sorry for the repetitions, but try to disassemble that damper; you will see the "hole" and you will also see the spoon dirty with white [residue], which you must clean. Let me know. If so, it depends on the too high percentage of synthetic in the white felt!!!!! Don't be surprised that it is a Schimmel.... let me know

Hi Paolo.

So, the problem can be divided into three points:

1) disassemble the damper;

on the action rail, the following are fixed: the hammer with a front screw, the damper with an upper screw, and the capstan with a rear screw. The hammer screw is covered by the escapement, while the damper screw is behind the hammer head. I could disassemble the hammer to have free access to the damper screw, but the escapement covers the hammer screw. What is the procedure for extracting the damper without damaging the escapement?

2) clean the spoon;

i cannot extract the capstan because the screw is behind it, but after extracting the damper, I could insert a brush from above to clean the spoon. I don't know if the spoon also needs to be adjusted.

3) replace the felt;

i think that a new felt and a suitable glue are necessary; what type of felt and what type of glue should I use?

How do you advise me to proceed?

Thanks, bye

The easiest thing is to pop the damper spring out of its seat and disassemble the damper itself. This way you can see the spoon that needs to be cleaned. The hole in the white felt can be slightly shaved with fine emery cloth. To replace it... you must have the same type of felt. Alternatively, you can use a cutter to unglue the felt and flip it over, if the hole is not very deep. You can use PVA glue (Vinavil), but only at the ends of the strip. Then reassemble the damper without the spring tension, otherwise you won't manage it, and then hook the spring back into its seat.

Good luck with the work

Paolo

pianoexpert wrote:

The easiest thing is to pop the damper spring out of its seat and disassemble the damper itself. This way you can see the spoon that needs to be cleaned. The hole in the white felt can be slightly shaved with fine emery cloth. To replace it... you must have the same type of felt. Or you can use a cutter to unglue the felt and flip it over, if the hole is not very deep. You can use PVA glue, but only at the ends of the strip. Then reassemble the damper without the spring tension, otherwise you won't succeed, and then hook the spring into its seat.

Good luck with the work

Paolo

Ok, thanks Paolo,

Merry Christmas