<html> <head> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; = charset=us-ascii"> <meta name=Generator content="Microsoft Word 10 (filtered)"> <style>  </style> </head> <body lang=EN-US link=blue vlink=blue> <div class=Section1> When I was in Reno, I attended a = class by a gentleman (Mr Vale?) from Austin</fo= nt>, Texas</fon= t>.  He has developed and patented a system for = installing vertical hammers which is as good as it gets.  I’ll try to = find his name and the handouts he had.  The system included many jigs for = setting the different parameters, such as bore, rake, etc.  His methods and = jigs are for sale (not cheap!).   He had many other jigs and tools = for sale, and he passed out his catalog to anyone who wanted it.  He = does a lot of upright restorations, and might be able to give a definitive answer.   I just found his name in the 2002 directory: Raymond = J. Vale, email: <a = href="mailto:rayvale@tooeasy.net">rayvale@tooeasy.net</a>. =          =       Paul McCloud       =       San Diego   -----Original = Message----- From: = pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org] On Behalf Of Greg Newell Sent: Wednesday, March = 12, 2003 9:14 PM To: Pianotech Subject: Re: uprights, = hammer boring   Keith, <x-tab>        </x-tab>I believe = that Newton Hunt wrote something about this a while back on this list. You = could search for it in the archives. If you find it feel free to repost. I'm = sure many would be interested. I seem to remember that bore distance was the = same as a grand in that butt flange center pin to string is the bore distance. = As far as rake goes I really don't remember. I don't replace a great deal of = hammers myself. <x-tab>        </x-tab>This = brings up a question for me that perhaps someone can answer. Although I don't = replace many sets of hammers on uprights I presently have occasion to replace a set = on an old Gulbransen upright. I tried to measure from the butt center pin to = the string and I just couldn't get a measuring device in there to take the measurement. Anyone have a tip on what I could use to get a good = reading? Might be too late for this set but I'd sure like to know for the next one. Greg At 05:28 PM 3/12/2003, you wrote: I gave the technical on = hammer boring at the chapter meeting, (with the back-up of the RPTs at the = meeting), and nobody could explain what the criteria would be for determining = hammer bore distance and rake for optimum performance on an upright. Sure, go by the = original is an easy answer but what if it looks as if somebody who "hadn't a clue" put those hammers on. I have 3 old uprights here, a 1909 = Smith and Barnes, a 1911 A.B. Cameron, and a 1906 Kohler and Chase. The first two, = the hammers shanks are close to parallel with the string plane, and the rake = is minimal. Or, worded differently, the bore distance is the distance from = the hammer flange center pin to the string plane. Rake is 1 or 2 degrees. = The Kohler has much more rake, 5+ degrees and the shank is at the similar = angle to the string plane so the hammer is square to the string plane when it = hits. Why? Should I be looking at the angle of the jack to the whippen at the start of = lift? The hammer butt/jack angle at let off? Or maybe it was something simple, like the little bit more clearance that = could be had by moving the action closer to the strings. Anybody? Keith Roberts --- Checked by AVG anti-virus system (<a href="http://www.grisoft.com/" eudora=autourl>http://www.grisoft.com</a>). Version: 6.0.459 / Virus Database: 258 - Release Date: 2/25/2003 </x-sigsep><x-sigsep>Greg Newell <a href="mailto:gnewell@ameritech.net" = eudora=autourl>mailto:gnewell@ameritech.net</a> </div> </body> </html>