Extra Capstan

[Richard Brekne]

I suppose useing a spring, it is similiar but not quite. In this case the spring
couples the key stick to the whippen, whereas the assist spring does not. So I
suppose this would have some direct effect on the key ratio and thereby the
action ratio as a whole. How much is another question.

But if one was to use a second capstan instead, well you would have two key and
action ratios. You could contrive things such that the one closest to the balance
rail pin would be effective up to the point the drop screw contacts the whippens
upper lever, and the other take care of the rest of the stroke.

That would allow for a greater mechanical advantage through about 90 % of the key
stroke then otherwise. During the rest of the key stroke (through letoff and
drop) you would loose that extra advantage, but I doubt you'd miss it much. By
that time the job of moving the hammer upwards is pretty much done anyways.
Perhaps at very soft play you might even notice the changeover.

Course it be a pain in the arse to regulate the back capstan... grin.

RicB

Farrell wrote:

> Is this not a principal similar to the helper springs on some wippen flanges?
>
> Terry Farrell
>
>
> > Hi folks
> >
> > Was dinking around today and got to thinking.... why not two capstans.
> > One to take you up to letoff drop, and one to finish the job as it were.
> > The immediate benifite would be to be able to design extra leverage in
> > to the system while not sacrificing anything relative to touch.
> >
> > I fooled around a bit with a upright jack return spring mounted in a
> > half way bored tuning pin bushing. Placed just in front of the capstan
> > and strong enough to help lift, but not so strong as to push the hamer
> > away from rest position. It got 4 grams off Downweight.
> >
> > Course any such contraption would defininatly get in the way of the
> > capstan adjustment, unless you could figure out a way to easily remove
> > and replace it... a slide mount or something.
> >
> > Anyways... seemed interesting enough so I thought I would throw it out
> > at you all
> >
> > Cheers
> >
> > RicB
> >
> >
> >
> > --
> > Richard Brekne
> > RPT, N.P.T.F.
> > UiB, Bergen, Norway
> > mailto:rbrekne@broadpark.no
> > http://home.broadpark.no/~rbrekne/ricmain.html
> >
> >
> > _______________________________________________
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--
Richard Brekne
RPT, N.P.T.F.
UiB, Bergen, Norway
mailto:rbrekne@broadpark.no
http://home.broadpark.no/~rbrekne/ricmain.html