[pianotech] Adding weight to Wurly Console action/keys

[Dean May]

>>I hate to say it, but Console pianos do not have "knuckles"! Are you
talking about Hammer Butt Leather?
Please explain what the heck is "...the nasty felt..." is.<G>  
 
Knuckles, schmuckles, you knew what I was talkin' about, right? :-)
{Thanks for the correction anyway}

Yes, nasty felt, that reddish brown stuff that is high friction. It's not
leather, its not the Baldwin corform. I don't know what it is, but it is a
problem. I'll send you a sample if you like. 


>> When you "..added about a 10 gram weight into the back of the key.." did
you weigh off the key on a scale to see how much down weight was on each
key? Or, did you just add it to all the keys, in the same place/manner and
assume that the down weight would be the same on each key?<G> 

I did a sampling of a half dozen notes down the scale. I put the sustain
pedal down to take the damper springs out of the equation, then I measured
down weights and up weights. I then added a balancing weight to the back of
the key and repeated my measurements. Then I added a weight to the wippen
and measured again. With both weights the down weight came up from low 40s
to upper 60s. Upweights, which is what I was most concerned with came from
below 20 to 40. I figured I could reduce the downweight a little by backing
off hammer spring tension. I also knew I wanted to reduce the damper spring
tension. I was hoping to end up with a downweight of about 50 and upweight
of 30. I was little shy of both targets, but it was still a big improvement.
Attached is spreadsheet with my preliminary measurements.

Of course the concern is that the end result will feel "too heavy" to the
pianist. I was counting on the increased upweight, reduced friction at
hammer butt and reduced spring tensions would counteract any increase in
heaviness and instead give the perception of better responsiveness. I was
very happy with the results. 

No doubt I could have spent double the amount of time and done a better job
of making sure all downweights and upweights were more uniform. But as has
been pointed out, it is not a concert instrument. I was looking to make it
better within a budget without taking the piano into the shop. I've done
some work taking mass out of a grand action, never have added mass into a
vertical action, though I have been sorely tempted many times over the
years. There isn't really anyone in my area that does this kind of work,
either, so I was pretty much on my own in working it out. 

But I have you guys! :-) Seriously, it was an exchange of emails in recent
months on adding weight to these uprights that fortified me enough to do it
on this job. Using that as a foundation and adding my own intuition of 30
years of working on pianos, I went for it. 

We have a lot of Wurlys in my area, maybe because Dekalb IL is only 4 hours
away. My experience with them over the years is that their wippens tend to
be sluggish. I think it is a combination of tight pinning and low wippen
mass. This is why I really wanted to add a little mass to the wippen. And
while it certainly would have been more craftsmanlike to drill the hole,
that would have added at least 2 more hours to the job. At least I drilled
the keys instead of using Jiffy leads. Do I get points for that? ;-)

I guess the point of the story is that if you can get passed being anal
retentive about doing "factory work" that no one who comes after you can
criticize, you can make a big improvement in the touch of these beasties
without a huge investment of time. I was willing to take the risk and do it,
and I am very happy with the results. If someone wants to look at the split
shot sinkers ten years from now and with self importance criticize my work
to the customer, that will be on their own heads. I feel good knowing I made
a big improvement for not a lot of money. 

This will not be my last such job, I can tell you that. Now that I know how
easy it is and how good the results are, I'll be doing it more. 

Del, I would love a little more info on adding weight to the damper heads.
How much weight and in what sections? I seriously considered doing that, as
I recall somewhere in the deep recesses of my aging brain it being
discussed. I even dug out Spurlocks notes on redoing dampers looking for
info on adding weights, but he doesn't discuss it. 

Thanks, guys, for your feedback, and for educating me enough over the years
to give me the confidence to try something new.

Dean
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