ACTION NOISE BABY GRAND

[coldfingers]

Hello
Would appreciate some advice on my Bluthner IV 1937, restored (I'm told) about 15 years ago by Bluthner in London.
Release of the keys in the most used areas produces a thump which I now find quite distracting.
I've had a look at the hammer rest rail etc with the action out and the felt is soft and not too indented.
The noise doesn't appear to originate from the keys themselves falling back to rest, and they don't seem loose on the pins.
Any thoughts on the source and the solution please ?
I'm in North Cornwall in case there's anyone with a recommendation of a local expert who might work on it.

[Barrie Heaton]

Depend if it a patent action or roller.

if a roller then it's most likely the rollers getting hard and banging down on the jacks and the jack slap button getting hard as well. the hammers should not be resting on the hammer rail when at rest.

if a patent action then lost of items to make a noise I would not dismiss the keys if the balance holes are enlarged thy will knock


Barrie

[vernon]

Could be the hammers are resting ON the hammer rest. They should sit clear of it

[Colin Nicholson]

Another thing.... If the key slip rail has warped slightly (or not adjusted right), this may cause a thump as the key comes back up; the rail should be bushed evenly/ not worn and no less than a 3mm gap hovering above the keys - found just behind the fallboard, running the whole length of the keyboard (looks like a quadrant trim). As a process of elimination, temporarily remove the rail and try it out. Wood of course is an excellent conductor of sound, and although the sound may appear somewhere else, it could actually be right under your nose. Depends also on the level of restoration - generally speaking, things like wooden rails are not replaced, just re-felted.

[coldfingers]

Thanks everyone for very helpful replies.
It's roller action, and the hammer shafts do sit on the hammer rail felt when at rest. If they shouldn't, then some serious regulation is needed, but I'm uncertain about this since there's no lost motion between depressing keys and hammers starting to lift.
I'll have a look at the slip rail but I'm no technician and dare not take things apart !

[Barrie Heaton]

Thanks everyone for very helpful replies.
It's roller action, and the hammer shafts do sit on the hammer rail felt when at rest. If they shouldn't, then some serious regulation is needed, but I'm uncertain about this since there's no lost motion between depressing keys and hammers starting to lift.
I'll have a look at the slip rail but I'm no technician and dare not take things apart !

if the hammers are sitting on the rail, you have lost motion and the action needs a good service call in a tuner who can regulate

Barrie

[Colin Nicholson]

The hammer shanks underside (not shafts, but I know what you mean), should hang about 3mm above the rest rail at rest, there must be a gap here, so the roller does the "resting" on the rep lever, not the shanks. The hammer rest rail is actually called a "staccato" rail, and used for mainly staccato/ short playing so the hammer can rebound slightly off the rest rail baize/ felt to take the blow. The thud will probably be causing this. Lost motion is different on a grand to an upright, and not as noticeable on grands because the jack passes through the rep lever, and the rep lever does some of the lifting work. If the jacks are more than 1mm below the rollers (tops of the rep levers), there will be lost motion. I'm estimating also the hammer strike distance may be wrong aswell.
As Barrie says, a full regulation (service) should sort the problems out. Your tuner will need a grand regulating rack to reset the hammers, so its best to ask if they do "grand regulation" - you will also need a decent flat table - about 4ft in length if the work can be done in your home; if not, the action may need to be taken away for the first parts of the regulation process.
Thereafter, pianos should be regulated every 3 years, and tuned every 6 months as a guideline/ depending on use.

[vernon]

It's taken 81 years for me to learn that the hammer rest is called the"staccato rail." crikey as Boris would say

[coldfingers]

Thanks again to everyone, really helpful.
Now I need to find someone in the outback of North Cornwall to sort it out, so if there's anyone with a recommendation that would be a great help. The tuner from the shop did a good job on first setting it up, but is too far away, and my experience of a local tuner wasn't brilliant.

[vernon]

try turning up a COUPLE of the capstans in the middle of the keyboard so the hammers hover 1/8th " above the hammer rest and see if that cures the trouble. If it does do the lot!
If it does not improve things,turn the hammers back level with their companions and get out the drawing board

[Colin Nicholson]

It's taken 81 years for me to learn that the hammer rest is called the"staccato rail." crikey as Boris would say

took me 20
quoted from a Mr A. Lawrence all those years back!

[Barrie Heaton]

It's taken 81 years for me to learn that the hammer rest is called the"staccato rail." crikey as Boris would say

took me 20
quoted from a Mr A. Lawrence all those years back!

I was told this when I was at college but forgot about it (like most things too much beer) till you pointed it out, but S&S call them Hammer rest pads, as most call it the hammer rest rail but the hammers don't rest on it. it may have been a City and Guilds question back in the 70s. Was it A, B, or C

Barrie,

[coldfingers]

Lifted the hammer SHANKS off the rest rail as suggested (only 1/2 turn needed), hammers all lined up and it's better but not much. It's a shame because the action seems good, light and even.
Time to call in an expert I guess, or exchange it for a modern instrument - would this be madness, or am I being over romantic about Bluthner ?
I know much of this is down to personal taste, but i don't think it sounded that bad in the showroom, so i'm wondering if noise from the action of any piano is going to bother me in a smaller room with a fairly low ceiling.
Too many variables but it's worth asking.

[vernon]

sorry to go back to "hammer rest" bit. On a grand it was always hammer rest to us. After all one rec-vered it with "hammer rest felt" Don't think Fletchers ever stocked " staccato rail felt."

[Colin Nicholson]

No harm in calling it either or (unless ordering felt!). I agree with what you say Vernon - perhaps I have confused its proper name for its purpose. In Reblitz - page 185/ section 13, there is a short reference to the purpose of the rail - hammers rebounding during loud staccato playing, but not resting on it. In Yorkshire, a teacake doesn't have fruit in it, and a pot of tea is a mug of tea. Try telling that to Geordies !