I think I'll stick with my initial supposition in 15.10.24 MMDigest
about John Tuttle's unknown brass tool being a piano hammer "iron".
The attached picture shows two models available from Schaff Piano
Supply, and although the example John showed differs in its geometry,
it doesn't appear to me that the holes are configured properly for
voicing needles.

Although John doesn't show dimensions or a comparative scale, the
holes have no apparent mechanism to lock the needles in a questionably
useful triangular pattern, and appear to be too large and shallow to
properly capture the typically available voicing needles.  I suppose
it's possible Bob Streicher did not finish this particular tool, but
I guess we'll never know.

Are there any MMD readers who purchased such a tool from Bob who could
further enlighten us?  Otherwise, perhaps a "real" piano technician
(RPT, not me) can weigh in on the subject.

John Grant

 [ Schaff Piano Supply Items #113 and #905
 [ http://www.mmdigest.com/Attachments/15/10/28/151028_094047_Hammer%20Iron.jpg