High(!) touchweight

[Charles K. Ball]

Dear Ron,

I would be interested to learn which knuckle placement this set of shanks
have, i.e. (Renner USA designations) "original dimension" (15.5mm),
"modified" (16.2mm), or "Hamburg dimension" (17mm) (which is also the
dimension used on new American Steinways [so-called "Improved"] and most
other major manufacturers I have examined).  If it is the "original
dimension", you could cut off the original knuckles and install new Renner
knuckles 1.5mm back from their location, saving about $600.00 on the Turbo
reps (sorry Lloyd) and taking little additional time once you are set up
for this operation.

If you have similar results to those I have experienced, you will be able
to remove one or two large leads from most of the keys and still have ideal
touch weight specifications.  You may have to increase the dip and perhaps
narrow the blow in order to achieve acceptable aftertouch, but you can
remain within factory specs, i.e. .420 dip and 1 3/4" dip as opposed to a
.390 dip and 1 7/8" blow.

We have made extraordinary transformations of quite similar situations to
the one you described through this method.  I now install only the
"modified" dimension (mostly on M's & L's) and "Hamburg dimension" (B's &
D's) shanks and save ourselves all the headaches you have experienced.

Regards,

Charles



>I've done a little bit of experimenting with capstan location using a gig
>similar to the one Del described. (See below for a description.) The
>results are interesting.
>
>NOTE: This is another B [#352489] that has the same leverage problem.
>Renner wips and shanks, NY hammers, Pratt-Read keyboard, "accelerated
>action" (read "lotsa lead!"). Essentially, the same keyboard as the one I
>mentioned before, only this one has Renner parts. The key bushing are new
>and eased correctly.  The centers on the shanks and wips are loose --
>probably will be re-pinned because they're outside of "shop tolerance."
>The piano was restrung this summer, oversized pins, original pinblock.
>Given that small amount of background....
>
>I removed capstans at No.s 1, 20, 21, 37, 51, 68 & 88, but because I had a
>short amount of time to work with, I only managed to get through the first
>five. On #1, the original capstan location downweight was 64, up was 36. I
>moved the capstan location 1/8" toward the balance rail and got 60 down,
>34 up.  Not bad, but not close enough to ideal for me. Note #20, moved
>1/8" only got me to 59 and 31. Note #21 was a distaster.  Had to move the
>capstan 1/4" and that *only* got me down to 59 and 30.  Note #37 went down
>to 60 and 38 with 1/8" movement.  And note #51 only got to 53 and 28 at
>1/8".
>
>Can't move capstans any more than 3/16" without the capstan contacting
>wood. 1/8" would be fine, except it means drilling out the capstan holes
>*oversized*, plugging and redrilling.  If I didn't oversize the old holes,
>drilling new ones would be straddling old and new wood.  If I used pine
>plugs (not dowels....plugs cut from scrapped keyboards), I *may* be able
>to get away with "normal"  sized plugs, but there's still a glue joint to
>deal with. (Have I started splitting hairs yet?)
>
>I'm contemplating the option of a combination of things; move the capstans
>no more than 3/16" *and* swap small keyleads for medium or large ones. The
>net result would be a lighter touch (improved leverage), but a slightly
>heavier keyboard (on the order of 150-200grams or 5-7 lbs, overall, is a
>guess).
>
>The other option is to install those "turbo" wippens from Renner.  I tried
>a few of those and they're pretty slick.  The manhours involved with
>re-pinning and regulating those wippens would be about the same as the
>current wippens (I don't think that stuff has been done yet).
>
>Anyone wanna hazard a guess at which route will take longer?
>
>Ron Torrella, RPT
>Piano Technician
>University of Michigan
>School of Music


Charles K. Ball, RPT
School of Music
The University of Texas at Austin
Austin, TX 78731
512-467-1535