Hammers behaviour

[iroveashe]

The hammers on my piano seem to bounce too much when they return to their resting position, and I can't figure out why that is, since it wasn't always like this and the least used keys, like the higher and lower registries don't have the same problem. I think it's something that happens normally with time (at least in uprights), but I have no idea how to fix it without spending a fortune on a technician.

I don't mind poking around the machine a bit, can someone tell me if this has a simple solution? Or any site where I could get info on the subject?

[richard black]

Broken check tapes? Hardened hammer rest rail felt?

[iroveashe]

Broken check tapes? Hardened hammer rest rail felt?

They're all in perfect state and the rest felt seems to be pretty even throughout the whole piano, so it wouldn't explain why some work well and others bounce so much.

[daniloperusina]

Do you mean that they bounce when you release the key?

Could be that the pins where the hammer butt is attached is too loose. Do you know what I mean?

I'll try to upload a picture...

[daniloperusina]

I've drawn an arrow to the pin I mean.

The friction that should be there is easily measured.
Do you know how to unscrew the hammer assembly?
Just underneath that pin there is a big screw. You'll see it if you look at the action of your piano from the front (sitting as you would when you play).

First unhook the strap. It has a blue color in the picture.
Then undo the screw. Then take the hammer assembly out, carefully.

Hold the hammer by the hammerhead in your hand. Check that the weight of the big screw makes the piece of wood where it resides move slowly down. If it moves like there is no friction, then the pin is way too loose.

[iroveashe]

I'll look at it tomorrow

Do you mean that they bounce when you release the key?

Yes, some do about 3 times as I can tell (probably 1 or 2 more but too fast to percieve it).

I'm going to try this tomorrow, thanks for the detailed explanation, though I don't think I see any blue in the picture.

[daniloperusina]

I've drawn one more arrow to show where the strap is attached. This needs to be unhooked.

If the problem is loose pins, than you'd have to call the technician. It's a highly qualified work.

[prongated]

Hold the hammer by the hammerhead in your hand. Check that the weight of the big screw makes the piece of wood where it resides move slowly down. If it moves like there is no friction, then the pin is way too loose.

[brag]
OMG I know exactly what you are talking about! I recently followed a piano tech. workshop at my conservatory where the piano technician explored the workings of the piano! I even got to replace one such pin during the workshop
[/brag]

[iroveashe]

I got as far as taking off the strap, the screw was beyond my reach. I noticed a difference between the hammers that bounce, and the ones that don't: the first have the space between the lower wood piece (I don't know the technical names) that moves upwards, and the lower part of the hammer that is moved forward by the first piece I mentioned; the space between them is larger in the ones that bounce. What I did was move the metal stick that is holding the check tapes a bit backward, and that seems to help, but not entirely solve it.

I guess I'll give up, since I have no money for a technician.

[brag]
OMG I know exactly what you are talking about! I recently followed a piano tech. workshop at my conservatory where the piano technician explored the workings of the piano! I even got to replace one such pin during the workshop
[/brag]

You're lucky, I can't seem to find anyone who teaches this kind of stuff. A guy even told me piano tuners are "in extintion".

[richard black]

Well, you've clearly got a good eye for finding the problem - now be brave and apply the same eye to working out how to fix it! A lot of these things are screwdriver adjustments in the action, so get yourself a suitable-looking screwdriver and have a go. When adjusting something, just bear a few basic rules in mind:

Most important - don't force the screwdriver in any direction as you might break something.

In case you are adjusting the wrong screw, make initial adjustments in an exact number of half-turns, keeping count as you go, so that you can restore the original setting if you decide you've made a mistake.

Check often to make sure you haven't accidentally upset some other adjustment or parameter.

Honestly, there's everything to be said for acquiring a little familiarity with the workings of your piano, and careful experimentation is by far the best way to acquire it.

[iroveashe]

Thanks for the encouragment Richard, I had given up but I'll open it again, at least to observe.

Is there a specific name for this sort of thing, like there's tuning and voicing, so that I can search and read more on the subject?

[richard black]

Is there a specific name for this sort of thing...?

Yes - regulation.