upright balance weight

[Keith Roberts]

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Hi Terry, questions on uprights? Not worthy, not worthy. Except I have =
paying customers who don't have room for a grand, love the old piano =
cases and want them to work well.=20

I think it is simpler if we look at the fact that the hammer weight has =
no effect. I hung the heaviest Wurzen felt Ronsen hammers on the thing =
and the DW was the same at the bass as the treble. The friction becomes =
equal note to note and less than on a grand because the friction at the =
hammer butt is basically nothing. This being the case, the leading is =
the same from note to note to achieve the same balance of the key and DW =
can be achieved this way. I don't like actions with a 56 gram =
downweight. Too heavy.=20

The key ratio is a 1.66 so I'm thinking the factory got the balance rail =
off by 1/8 inch. You have to double the balance rail mistake soI figure =
a 5mm capstan move should do it. By tilting the capstan I should pick up =
3 grams DW. The 5 mm will be  along the top of the key and the top of =
the capstan will move 2 to 3 mm in relation to the sticker. Total I =
expect to pick up 4 to 5 grams of DW.  There is room on these stickers =
to come that far forward but I can always remove the rail and take out =
some wood to move the bottom rail where ever I want. That's the beauty =
of long stickers.

I certainly don't want to lighten the action by adding lead. Removing =
lead might make it free wheel, not enough mass. I want to see if =
changing the geometry to solve the DW problem will give it the "snap" =
I'm looking for.

Thanks for your interest Terry. No pictures yet. I'll have to get some.

kpiano

  I don't know what might be a good BW for an upright. I have lots of =
questions about balancing an upright action. Rumors have it that David =
Stanwood is looking into upright action balancing. In your case you have =
a lot of UW, if you don't have too much lead in the keys now, you could =
add a little lead to the front of the key to get the DW down to 50g or =
so and still have over 30g UW. How does the capstan/wippen-heel-cushion =
interface line up - would moving the capstan help or hinder? Also, what =
is the status of you butt springs - the tension there will affect things =
also.

  Do you have a picture of your Knabe? 1890s Knabes are just awesome!

  Terry Farrell

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