Renner "Turbo Wippens" ?

[David ilvedson]

BW=(DW + UW)/2...What does that show us?  I am not particularly 
up on Stanwood's "balance weight" work.  Was there a recent 
article in the Journal I missed?  With a 50 gram DW and a 25 
gram UW we have 37.5 BW which I would assume is a good balance 
weight?  With a 60 gram DW and a 30 gram UW we would have a 45 
gram BW.  A 60 DW and 20 UW would be 40 BW.  

Thanks in advance...

David ilvedson, RPT
Pacifica, CA


> We all know the difference between a mass problem and a friction problem.
> Each has it's own diagnosis and treatment. Because each is dealt with
> separately, we should start thinking of them as separate attributes as
> early as we can. If we want to separate mass from friction, by far the most
> expedient amd practical way is to infer these two quantities from UW/DW. As
> David Stanwood has laid out, BW=(DW+UW)/2 and Friction=(DW-UW)/2. (Are
> there any people here who should be over with the rocket scientists, BTW.)
> 
> As I mentioned earlier, the rep spring's purpose is to counterbalance
> action mass. FWeights are the conventional way to do this. With bad
> leverage, the resulting friction can widen the spread between DU and UW,
> but your first problem is mass anyway. It doesn't matter whether you are
> pushing down high DW resulting from bad leverage or heavy hammers, or
> whether you're bringing an UW up above 20g because someone else has
> overleaded the keys in repsonse to the same problem. With either FWeights
> or helper springs, you're changing the balance of weight between the front
> and back halves of the key.
> 
> Usually, as soon as the helper springs go on, certain amounts of lead (FW)
> are soon removed from the key fronts. The exact amount of counterbalancing
> done by the springs can be further adjusted individually, to acheive the
> exact amounts we're used to acheiving with leads. (A set screw design
> exists for this, BTW.) But the results are no different in an action with
> "good or bad geometry": the helper spriongs goes on, the lead comes out.
> Certainly, that's the way a Viennese action should feel. But you'll be just
> as glad to pull lead out of an action with bad leverage.
> 
> To tell the truth, it's less expensive to correct bad leverage and solve
> the problem at its source (either by rehanging the hammers on more
> favorable shnks, or moving the cap line), than it is to purchase the new
> Tarboy Whips (which as we understand change neither the hammer mass nor the
> overall leverage). But to do this you need to have a few more measurements
> on your worksheet than just DW (or maybe even UW). I am much in awe of the
> two primary rebuilders whom Loyd Meyer is relying on for action advice. But
> any paper which outlines the use of the spring balancing rep without
> advising on its effect on weight and friction as matters separately read
> and corrected, is bound to be a little confusing. At least that's what the
> Renner sheet on the inbstallation of Turbo Reps was for me.
> 
> I would straighten out this confusion by genrealizing: The helper springs
> should be used the way lead is, to counterbalaince the back half of the
> key. Although the springs may change the feel of and action with bad
> leverage or mass, they will not change those aspects of the feel having to
> do with bad mass or leverage. Helper springs should  not be chosen because
> they can correct bad leverage. They won't. You may be able to use the
> change in feel they may offer in a situation of bad leverage, but don't use
> them because you think they'll clear up a leverage or hammer weight
> problem. They won't.
> 
> Bill Ballard, RPT
> New Hampshire Chapter, PTG
> 
> "Round here we don't talk unless we can improve in the silence."
>     Ron Rude, local Public Radio Commentator.
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David Ilvedson, RPT
Pacifica, CA
ilvey@jps.net