[pianotech] Clunky Noises

[Joseph Garrett]

Comments interspersed <G>

Joe Garrett, R.P.T.
Captain of the Tool Police
Squares R I


> [Original Message]
> From: David Nereson <da88ve at gmail.com>
> To: <joegarrett at earthlink.net>; <pianotech at ptg.org>
> Date: 3/9/2011 12:14:18 PM
> Subject: Re: [pianotech] Clunky Noises
>
>
> ----- Original Message ----- 
> From: "Joseph Garrett" <joegarrett at earthlink.net>
> To: "pianotech" <pianotech at ptg.org>
> Sent: Tuesday, March 08, 2011 8:55 PM
> Subject: Re: [pianotech] Cluinky Noises
>
>
> > No where do I see where any felt, of any consequence, has been 
> > replaced, wth the exception of the sticker felt.
>
>         It's lifting up the wippen, with the back of the key 
> held down, and letting the wippen and its extension (sticker) 
> drop onto the capstan, that makes the loud clunk.  Thus the 
> reason for trying new sticker cloth.

Even tho you are checking in this manner, the old, compressed felt can
still be transfering the energy/noise into the key bed. 
>
> >> I am curious what type f sticker system and how the felt is 
> >> glued on.
>
>         It's the type found in, I'd say, 90% of old uprights --  
> the long extensions with a sticker tongue and sticker tongue 
> flanges screwed to a sticker rail, i.e., not dowel capstans, not 
> stickers that are pinned to the keys, not rockers.  I'm 99% sure 
> the felt is glued on with hide glue, as was almost everything 
> back in 1918 (when this one was built).

What I was asking was what kind of contact felt configuration. i.e. a
simple square glued directly to the bottom of the sticker? Or, glued on the
side of the sticker and wrapped around the end and glued to the other side
of the sticker? If it was the first type, then I would suggest the second
way will be quieter. Of course, there are some stickers that will not lend
to that way of attatching the felt. The down side to that system is that it
takes a long time for the felt to compress and reach and equilibrium, in
terms of lost motion.<G>
>
>
> >>The reason for felt, (with the exception ofthe hammers), is to 
> >>quiet the mating parts. I would suggest, new key frame felt, 
> >>as a start. then the hammer rail felt, including the hammer 
> >>rail rest felt, (what everyone likes to add felt to.<G>)
>
>     Yes, I may go that route, but I thought there might be some 
> simpler thing I was missing that could be attended to first. 
> The hammer shanks returning to the rest rail don't make much 
> noise.  The back rail cloth may be a culprit, but I don't think 
> the balance and front rail punchings are, since even when 
> holding the key immobile, the wippen/extension clunks when 
> lifted and dropped onto the capstan.
>     The hammer rail rest felt (by which I assume you mean the 
> cushions between the bottom of the hammer rail and the action 
> brackets) comes into play only when using the soft pedal.

No. If the felt is hard/compacted, etc., it will still transfer the "noise"
into the action brackets, which, in turn will send it to the key bed and
the rest of the vibrating body, otherwise known as 'the piano'.<G>
>
> >>Possible ways to quiet such noises, is to isolate the action 
> >>from the key bed/sound board as best as possible. I've added 
> >>felt to the tops of the action bracket bolts...(of course, I 
> >>had to reset them lower, to maintain the strike points).
>
>         You mean adding felt to the tops of the action REST 
> bolts?  I've seen some makes where the tops of these have 
> leather, installed by the factory. 

Yup! Only I've use action cloth instead of leather. Worked.<G>
>
> >>Getting rid of the "clunks" can really be challenging. There 
> >>are some pianos that simply defy any attempts, so don't 
> >>promise the farm.<G>
>
> > Regards,
> > Joe
> > Joe Garrett, R.P.T.
> > Captain of the Tool Police
> > Squares R I
>
>         Well, yes, I did tell her that all actions make a little 
> noise and I won't be able to make it entirely inaudible.  But 
> replacing hammer rail cloth and back rail cloth sound like the 
> two best things to do besides replacing the sticker cloth.
>     --David Nereson, RPT