Excessive friction

the damper mechanism pins and their respective springs must be checked

Now I wonder how to see if the problem is the spring being too "hard" or the fork needing boring and the pin needs changing, as I tried holding the damper from the fork (without the spring) and it moves easily from one side to the other with its own weight (like a scale).

Is it probable that over time the spring has hardened?

What do you advise me to do?

Now I wonder how to see if the problem is the spring being too "hard" or the fork needing to be bored out and the pin changed, as I tried holding the damper from the fork (without the spring) and it moves easily with its own weight from one side to the other (like a scale)

Is it probable that over time the spring has hardened?

What do you advise me to do?

In addition, I would like to understand how to insert images because (in my modest opinion) the felts need to be changed

It depends on the manufacturer's choice. I don't remember your piano brand. However, for example, Schimmel uses robust springs, and you can feel the difference more between the weight of the key depression when free and when it encounters the damper. It is not advisable to modify the springs, because the choice of gauge may have been made based on the length of the iron lever, the position of the damper, etc. The only thing you can check is the sliding of the spring and, if necessary, graphite the groove where it slides.

Alright, I will try to put graphite on the felt

In fact, the felt is almost completely white on some dampers...

Can you extract a pencil lead and rub it on its side from the round part?

I have a Bechstein model 8, not for long

NOT ON THE FELT! In the notch of the wooden lever where the spring slides!!!!!!!

LIQUID GRAPHITE

It must be applied with a slightly [damp/light] brush. If it remains difficult, you must hire a technician

NEVER TOUCH THE FELTS!!!!!!

You need to free the spring, CLEAN IF THERE IS DIRT that prevents sliding and apply GRAPHITE. LITTLE GRAPHITE!

Of course, with "felt" I didn't mean the stuff that goes on the strings...

I meant the little piece of felt attached inside the recess where the spring pushes the damper. Right?

I would like to insert an image to make it clearer but I can't figure out how to do it...

And then what is the difference between felt, cashmere, and "diablement" woven cloth? Why is one used rather than another for certain purposes?

Which of these would reduce friction if used in moving parts? (e.g., keyboard end, damper groove, etc...)

it cannot be said in two words. Cashmere of different thicknesses is used for the pinblock gaskets and for the keyboard slots. White diablement is not used, which instead resists compression well (stand heels)

Agreed, Maestro Paolo

So if I wanted to change the key end felt that pushes the pilot (on my upright the pilot is screwed to the heel), is it better to use diablement?

Obviously respecting the thickness...

Unfortunately, the current one is non-homogeneous and has brown spots (maybe old mold?)

It is not clear what you have to do! The key end felt does not push the repetition lever and the repetition lever is not screwed to the heel! Everything needs to be examined because everything is being modified, and doing only one thing does not resolve the dissatisfactions. The functioning of the piano is a "WHOLE" and the whole is not simply the sum of its parts. Adjustments and replacements are interdependent. A technician must see what is necessary and what is not, even in relation to other parts to be replaced or not.

My goal was to lighten the action, especially that of the dampers; then, gradually, I discovered that the piano presents other small problems, such as old damper felts, damaged key felt, and an escapement of 5 mm (I adjusted it to 2 mm for bass and mid ranges and 1.5 mm for the treble)

I would therefore like to resolve these problems; in case things go wrong, I will call a technician anyway to fix everything

As soon as I can, I will post some photos to give a better idea

The technician must reconsider everything. ATTENTION IF YOU REPLACE THE HAMMER RAIL, ENSURE THE OLD ONE IS RETURNED: If the escapement is far from the strings, the hammer rail has surely been shaved down. It is necessary to trace back to the original measurements of the hammers. Adjusting is not enough if the geometry of the action has been altered. Write down everything that is done and how. For this reason, I issue a report with color photos, noting, illustrating, and explaining all technical interventions and the measurements adopted. This adds value to the instrument in case it is resold.

Unfortunately yes, the shaving was done and perhaps the previous regulation was left as it was...

What can I do now while waiting for the technician?

Is it enough to have fixed the escapement or is it necessary to also adjust the hammer-string distance and the pilot?

Currently, the distance is 50mm for the bass and 47mm for all other hammers up to the treble (with the previous escapement of about 5mm)

The hammer must be replaced. The entire geometry is altered. Both the striking point and the hammer are altered, also due to age; it will never sound good again. Less felt, a certainly different shape with rounded trebles, "remaining" felt closer to the wooden core and therefore a harder sound. It is not a matter of voicing the hammers, as the technician might perhaps tell you. The structure of the hammers is altered, making it impossible to act on the various zones (shoulders, apex, etc.). While at it, one must take a look at the keyboard (bushings and guide pins), the heels, the nut skins (if it is an upright piano), the dampers and their respective felts.

By returning the regulation to its original values, a loss of energy is obtained due to the alteration of the alignment of the parts.

The condition of the strings must also be taken into consideration.

If you want, let me know which piano it is and send me some photos.

I have understood, therefore, the reason why now that the escapement is "correct," the hammer, after tripping, does not move back a little as it should but remains almost stationary...

Anyway, I will post the photos this evening

Thank you very much for the time dedicated so far

If I try to upload images, they don't open on the site...

In what format should I upload them?

Or can I send them in private messages?

you can send them to me on whatsapp 3393395980