[pianotech] Steinway back checks

[David Skolnik]

Larry -
I think everyone should experience the exquisite 
thrill of 'trimming' a large skin (not talking 
about Doremus's approach) to figure out areas of 
varying thickness and grain direction.  After 
that, I would (have been) using nicely consistent 
Ecsaine synthetic buckskin, from Pianotek (listed 
in their catalog). I'm not sure if it's got 
hidden flaws that show up the day after the 
warrantee ends, but it is remarkably consistent, 
both in thickness and texture.

The biggest challenge is coming up with a method 
of cutting the correct width strips for the 
particular width checks (without invoking the 
Doremus approach).  I use an Olfa rotary cutter 
(on an appropriate surface) and a piece of brass 
or steel stock that's large enough to keep my fingers away from the cutter.

I don't think it's that difficult to achieve the 
correct tautness.  Once I've cut the long strips 
from the sheet, I cut individual pieces (to a 
predetermined length that will be slightly 
over-size, requiring a little trimming).  I use 
hide glue, fairly thick, to glue the skin to the 
top of the check.  By the time I've finished 
that, (and, after checking to see that I still 
have all 11 fingers), I glue the bottom, pulling 
it reasonably taut.  I've used a few different 
kinds of clamping procedures, for example, I've 
used a set of Schaff's Key Bushing Wedge Clamps 
((P.48 - #151) that I've modified by changing the 
angle of the feet and compressing, so that the 
clamp actually works in an inward direction 
(rather than outward, as originally purposed).  I 
haven't, but probably will (upon next use) glue a 
small piece of something to the inside surface of 
the active foot, to avoid a bit of dimpling.  I 
also have used some mini-spring clamps (plastic) that I got somewhere,

When try, I just trim the excess from the bottom 
(again, avoiding the Doremus method), and, voyla! (voila!).

Clearly, you would want to be sure that all the 
remaining aspects of the backcheck were sound, 
such as wires and backcheck felt.  In fact, it 
might be an interesting issue to pursue to 
consider the ideal degree of resilience of the 
backcheck system (wire, felt, skin) as it contributes to effective checking.

Of course, it would be smart to master the 
process of installing new backchecks as well.

Good luck.

David Skolnik, RPT
Hastings on Hudson, NY



At 12:25 AM 9/12/2012, you wrote:
>I’m including an image of the original back 
>check.  As you can see, the back check head 
>quite large.  New ones (three different types 
>shown) have a totally different physical 
>dimension to the point that it’s beginning to 
>look like it would be faster to simply recover the existing back check heads.
>
>If I were to go that route  ........... and 
>aside from getting the grain of the leather in 
>the right direction  ............    is it 
>critical to get the leather at a consistent 
>tightness to get some reasonable checking effect??
>
>A procedure involving a clothes pin has been suggested.  Comments??
>
>P9111268a
>
>
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