Rebushing centers

[Robin Hufford]

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Hello Barbara,
     I think it is vital to properly shrink and stabilize  the bushings 
after installation.  Otherwise, you will be where you are now with the 
inadequate Steinway parts (something ridiculous and telling in itself 
for a company in business doing this for 150 years,)  you refer to in 
recent posts, that is, the friction will not be stable and the hammer 
will also wobble causing a loss of power. 
     I have used shrinking fluid combinations with proportions ranging 
from 50/50  to 75/25 or so, water and methyl alcohol and had good 
results. Although, I have had, on occasion, a need to do some over, as 
some were still, after drying, loose.  These were then rendered 
acceptable after another treatment. 
     An interesting new possibility, which had occurred to me one day as 
I was waiting for a conventionally treated set to dry and is, as far as 
I can tell, a completely new technique since I have not seen it referred 
to anywhere or heard any discussion about it elsewhere,  I decided to 
try  on a set of Tokiwa  shanks which had a very soft, unstable bushing 
that responded to pining exactly as you describe with the Steinway, is, 
perhaps, better.  
       This method uses water thin CA glue thinned even further to about 
about a 90/10 acetone/glue mix.  It occurs to me now,  as I write this,  
that it may work better if a little methyl alcohol is added as a wetting 
agent, if possible, although I haven't done this.  There may be 
complications if alcohol is used which I am unaware of at the moment.
      As you know, of course, the CA rapidly sets and this 
characteristic obviates the need for the prolonged drying necessary when 
using water.   One can vary the mixture as desired to control its 
effects,  but if too much CA is used it will make the bushing so hard 
that it will click and this defeats the purpose of  its use.  Too little 
and there is not enough stability induced in the bushing. 
      On the piano I tried this on I have had very good results;  the 
pining is stable and there was a noticeable increase in power.  I tried 
at first to apply it simply by dripping the mixture onto the bushing:  
this does have an effect, but, eventually, I removed the pining, wetted 
the bushing and then reinstalled a pin.   Perhaps,  as I indicated 
above, a wetting agent like methyl alcohol will make it possible to do 
this without even removing the pining.   All of the flanges on this 
piano had already been repinned, some twice or even three times.  They 
had progressively loosened as you described earlier. 
       Judging from your recent posts you are considering rebushing the 
inadequate Steinway shanks you have referred to.  I would try this 
technique before rebushing were this problem one I had to solve.  I 
think, once resigned to rebushing, you have nothing to lose. 
Regards, Robin Hufford

Barbara Richmond wrote:

> Here's a question for you who rebuild action parts:
>  
>  
> I've rebushed flanges before, you know, one here or there, but have 
> never done a whole set.
>  
> Are there any secrets besides just plain old rebushing?  For example, 
> do you shrink the bushings after you've put them in?
>  
> Thanks,
>  
> Barbara Richmond, RPT
>  
>  


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