test _____ From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of David Skolnik Sent: Wednesday, September 12, 2012 8:55 AM To: Larry Fisher RPT; pianotech at ptg.org Subject: Re: [pianotech] Steinway back checks 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 -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20120912/ecbbc80d/attachment-0001.htm> -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: image/jpeg Size: 188625 bytes Desc: not available URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20120912/ecbbc80d/attachment-0001.jpeg>
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