<font color='navy' size='2' face='Comic Sans MS, sans-serif'>David<br> <font color="#000080" style="font-family: 'Comic Sans MS', sans-serif; font-size: 10pt; ">Comments below in blue</font><br> <div style="font-family: 'Comic Sans MS', sans-serif; font-size: 10pt; color: navy; clear: both; "><font size="1" color="royalblue"><b><font face="Georgia, Times New Roman, Times, Serif"><font color="black"><font color="mediumblue" face="Comic Sans MS, sans-serif">Dale Erwin R.P.T.<br> </font></font></font></b></font><font color="darkgreen"><span style="font-style: italic;"><b><font size="1"><font size="1"></font><font size="1" color="crimson" face="Comic Sans MS, sans-serif">Phone: 209-577-8397</font><br> <font color="darkgreen"></font></font></b></span></font><tt><tt><font color="darkgreen"><br>  </font><br>   <font size="2"></font></tt></tt><br> <br> </div> <br> <br> <div><font face="arial, helvetica" size="2">-----Original Message-----</font><br> <font face="arial, helvetica" size="2">From: David Love <davidlovepianos@comcast.net></font><br> <font face="arial, helvetica" size="2">To: pianotech <pianotech@ptg.org></font><br> <font face="arial, helvetica" size="2">Sent: Sun, Aug 26, 2012 8:18 pm</font><br> <font face="arial, helvetica" size="2">Subject: Re: [pianotech] action ratio</font><br> <br> <div id="AOLMsgPart_1_e5c249e7-52c2-488c-acd0-e82dc9aad201"> <div class="WordSection1"> <div class="MsoNormal"><font face="arial, helvetica"><span style="font-size: 11pt;">The problem, as far as the formula is concerned, is that the .040, .050, .060 do not comport with the formula requirements (I assume the equality was based on something).  And your point is suggestive of the fact that the bit of key travel is not really the critical factor.  Rather, it is jack clearance from some yet unknown starting point.</span></font><font color="#0000cd"><font face="arial, helvetica"><span style="font-size: 11pt;"> By starting point you are meaning and assuming a 1.5 mm L.O. In that case the </span><span style="font-size: 14.399999618530273px;">After-touch</span><span style="font-size: 11pt;"> starting point is from the moment the jack touches the reg button and rep.lever engages its drop screw.</span></font></font></div> <div class="MsoNormal" style="font-family: arial, helvetica; font-size: 10pt; "><span style="font-size: 11pt; "> So aftertouch for the sake of that formula may be something other than what we think of as it relates to the thickness of the cardboard placed underneath the key.  That’s the main point of the question. <font color="#0000cd">Yes it could be.</font></span></div> <div class="MsoNormal"><font color="#0000cd"><font face="arial, helvetica"><span style="font-size: 11pt;"> I am liking the direction of this discussion and am </span><span style="font-size: 14.399999618530273px;">contemplating</span><span style="font-size: 11pt;"> this as well as you. I think it should be possible to have nice regulation based charts that have variable specs based on Action ratio </span><span style="font-size: 14.399999618530273px;">just</span><span style="font-size: 11pt;"> as Stanwoods hammer weight charts have </span><span style="font-size: 14.399999618530273px;">differing</span><span style="font-size: 11pt;"> hammer weight lines that seem to correspond with and work well with certain action ratios. Is this where you are going?</span></font></font></div> <div class="MsoNormal" style="font-family: arial, helvetica; font-size: 10pt; "><span style="font-size: 11pt; "><font color="#0000cd"> </font></span></div> <div class="MsoNormal" style="font-family: arial, helvetica; font-size: 10pt; color: black; "><span style="font-size:11.0pt;font-family:">Regarding ideal specs and action ratios (let’s put aside for the moment that the method of determining the ratio is something of a debate), there is no getting around the fact that a certain action ratio will tend to produce a particular regulation or combination of dip and blow, all other things being equal, i.e. let-off, aftertouch, jack position, knuckle diameter, capstan angle perhaps…).  If your ideal is 45 mm with .390” dip  (or 9.9 mm to keep the units the same), then you will only get that regulation with a particularly action ratio. </span></div> <div class="MsoNormal" style="font-family: arial, helvetica; font-size: 10pt; "><span style="font-size: 11pt; "><font color="#0000cd">For sure or with in some small deviations plus or minus.</font></span></div> <div class="MsoNormal"><font face="arial, helvetica"><span style="font-size: 11pt;"> You won’t get that with 5.0 and you won’t get that with 6.5 unless you alter the let-off or the aftertouch and at both extremes that is likely going to be detrimental.</span></font><font color="#0000cd"><font face="arial, helvetica"><span style="font-size: 11pt;"> Understood. Meaning low ratio of 5 to 1will require  a shorter blow and longer key travel to </span><span style="font-size: 14.399999618530273px;">cycle</span><span style="font-size: 11pt;"> thru after touch and a 6 to 1 plus ratio will require longer blow and shorter dip as do many Stwys,Baldwins, Mason Hamlins etc.</span></font></font></div> <div class="MsoNormal" style="font-family: arial, helvetica; font-size: 10pt; color: black; "><span style="font-size:11.0pt;font-family:"> </span></div> <div class="MsoNormal" style="font-family: arial, helvetica; font-size: 10pt; "><span style="font-size: 11pt; ">Now I think that 9.9 mm dip, or let’s just say 10 mm for ease here, and 45 mm of blow is a good target. <font color="#0000cd"> Sure...that was my point.</font> So my question is, in your experience, what action ratio is most likely to produce that without any fudging and further, what standard of cardboard punching thickness key travel are you using, ideally anyway.</span></div> <div class="MsoNormal"><font color="#0000cd"><font face="arial, helvetica"><span style="font-size: 11pt;">A 5.5 to 1 ratio seems to work out the regulation specs/ numbers I/We referred to. I typically don't use the cardboard method exclusively but use to do some checking, but I like the idea as a very idiot proof way to set a uniform feel <u>even if</u> the actual key travel varies a few thou. from note to notes. ie </span><span style="font-size: 14.399999618530273px;">inconsistency</span><span style="font-size: 11pt;"> in everything from capstan and knuckle line to the actual accuracy of the regulation itself. Know what I </span><span style="font-size: 14.399999618530273px;">mean</span><span style="font-size: 11pt;">?</span></font></font></div> <div class="MsoNormal"><font color="#0000cd"><font face="arial, helvetica"><span style="font-size: 11pt;">Dale Erwin</span></font></font></div> <div class="MsoNormal"><font color="#0000cd"><font face="arial, helvetica"><span style="font-size: 11pt;"><br> </span></font></font></div> <div class="MsoNormal"><font color="#0000cd"><font face="arial, helvetica"><span style="font-size: 11pt;"><br> </span></font></font></div> <div class="MsoNormal" style="font-family: arial, helvetica; font-size: 10pt; color: black; "><span style="font-size:11.0pt;font-family:"> </span></div> <div class="MsoNormal" style="font-family: arial, helvetica; font-size: 10pt; color: black; "><span style="font-size:11.0pt;font-family:">David Love</span></div> <div class="MsoNormal" style="font-family: arial, helvetica; font-size: 10pt; color: black; "><span style="font-size:11.0pt;font-family:"><a href="http://www.davidlovepianos.com" target="_blank">www.davidlovepianos.com</a></span></div> <div class="MsoNormal" style="font-family: arial, helvetica; font-size: 10pt; color: black; "><span style="font-size:11.0pt;font-family:"> </span></div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; border-style: solid none none; border-top-width: 1pt; border-top-color: rgb(181, 196, 223); padding: 3pt 0in 0in; "> <div class="MsoNormal"><b><span style="font-size:10.0pt;font-family:">From:</span></b><span style="font-size:10.0pt;font-family:"> <a href="mailto:pianotech-bounces@ptg.org">pianotech-bounces@ptg.org</a> [<a href="mailto:pianotech-bounces@ptg.org?">mailto:pianotech-bounces@ptg.org</a>] <b>On Behalf Of </b>Dale Erwin<br> <b>Sent:</b> Sunday, August 26, 2012 7:32 PM<br> <b>To:</b> <a href="mailto:pianotech@ptg.org">pianotech@ptg.org</a><br> <b>Subject:</b> Re: [pianotech] action ratio</span></div> </div> <div class="MsoNormal" style="font-family: arial, helvetica; font-size: 10pt; color: black; "> </div> <div class="MsoNormal" style="font-family: arial, helvetica; font-size: 10pt; color: black; "><span style="font-size:10.0pt;font-family:">Last Sat. Laroy Edwards and I taught a joint class in my shop to members of several local chapters in the region. Great fun and the Head piano Meister at 84 yrs young; ... was on his game. </span></div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:">  I had the pleasure of sitting in his "<u>after touch class".</u> where He clearly defined after touch. </span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:"> </span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:">  Short story is that after touch begins as soon as the jack escapes the knuckle. How far it moves past that is the real after touch number/distance/feel. One limiting factor to jack movement and hence after touch is determined by the total length of the repetition lever slot. The jack cannot move beyond the rep.lever slot stop with out the jack tender binding and then breaking off. Bummer. Ca glue please anybody.</span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:"> </span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:">  Another limiting factor is that the jack must escape enough that it DOES NOT have opportunity to dance with the knuckle and do the mister booble head thing. With repetition in mind the farther the jack escapes the farther it has to travel back, and we all know this of course will slow repetition.</span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:"> </span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:">   So within those  parameters in mind some variability is allowed/acceptable based on subjective feel. I'll leave it at that for now. Using Davids cardboard method to just sense jack escapement is quite good I think.  Many techs that use this method state a preference like..... "I like .040....050 ...060. cardboard placed on top of the front punching as there sensory gauge" </span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:"> So these are small parameters to be sure but we and our pianists clients live in the realm of the subjective. Some like dip/key travel deep some like it so short that mister bobble head can almost dance and these folks, oddly enough....have learned to control it.</span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:"> </span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:"> </span><span style="font-family:">Dip.</span><span style="font-size:10.0pt;font-family:"></span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-family:">  This Sticky wicket wording to me always needs clarification</span><span style="font-size:10.0pt;font-family:"></span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:">   So this means to me overall key travel top to bottom. How we measure it will be confusing unless we speak specifically how we do that. In setting up any action regulation parameters I am  looking for roughly those numbers David suggests. ie. 45mm or 1 3/4 blow....Let off at approx. .050/1.3mm,  </span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:">(I like it close.) and a .390 dip.  I measure that just in front of the key pin & right under where the finger touches the key much of the time with a direct measurement gauge. (the Erwin dip gauge)</span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:"> ( see picture.)  Now I realize that the key travel depth can vary given the wide variance of action ratios, typically 5 to 6.5, but actions that fall within what we all refer to as normal compliance, fall into these numbers routinely. So its at least a starting point when looking for parameters.</span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:">Other folks measure at the very front of the key with a metric ruler. Whatever works</span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:"> </span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:"> Another consideration is that the standard green front rail punching available can easily squish .035. </span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:">That seems like a lot don't ya think? This is not a promotional but the fairly new Cresendo punching compress a very predictable .015. So,.... over all key travel can be set very precisely. Some don't like the feel but that's another story. So overall dip/key travel set from a basically static method changes quite variably under different dynamic ranges/key pressures with the green squishy punching. </span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:"> So now;... what is the dip really?</span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:">  I just wanted to clarify some other reasons why Jim might be a bit confused since I was thinking about it lately.</span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal"><span style="font-size:10.0pt;font-family:">  </span></div> </div> <div style="font-family: arial, helvetica; font-size: 10pt; color: black; "> <div class="MsoNormal" style="margin-bottom:12.0pt"><span style="font-size:10.0pt;font-family:"> </span></div> <div> <div class="MsoNormal" style="margin-bottom:12.0pt"><b><span style="font-size:7.5pt;font-family:">Dale Erwin R.P.T.<br> </span></b><b><span style="font-size:7.5pt;font-family:">Erwin's Piano Restoration Inc.</span></b><b><span style="font-size:7.5pt;font-family:"><br> </span></b><b><i><span style="font-size:7.5pt;font-family:">Mason & Hamlin/Steinway/U.S. pianos<br> </span></i></b><b><i><span style="font-size:7.5pt;font-family:"><a target="_blank" href="http://www.Erwinspiano.com">www.Erwinspiano.com</a></span></i></b><b><i><span style="font-size:7.5pt;font-family:"><br> </span></i></b><b><i><span style="font-size:7.5pt;font-family:">Phone: 209-577-8397</span></i></b><b><i><span style="font-size:7.5pt;font-family:"><br> </span></i></b><span style="font-size:10.0pt;font-family:"><br> <tt> </tt></span><span style="font-size:10.0pt;font-family:"><br> <tt>  </tt></span><span style="font-size:10.0pt;font-family:"></span></div> </div> <div class="MsoNormal" style="margin-bottom:12.0pt"><span style="font-size:10.0pt;font-family:"> </span></div> <div> <div class="MsoNormal" style="margin-bottom:12.0pt"><span style="font-size:10.0pt;font-family:">-----Original Message-----<br> From: David Love <<a href="mailto:davidlovepianos@comcast.net">davidlovepianos@comcast.net</a>><br> To: pianotech <<a href="mailto:pianotech@ptg.org">pianotech@ptg.org</a>><br> Sent: Sun, Aug 26, 2012 11:51 am<br> Subject: Re: [pianotech] action ratio</span></div> <div id="AOLMsgPart_0_cea1fe86-c92b-4ac4-ae2e-1a399da24379"><pre style="background:white"><tt><span style="color:black">I don't quite think it's apples to oranges because for any given action</span></tt></pre><pre style="background:white"><tt><span style="color:black">ratio there will be at least a limitation to the regulation specs or the</span></tt></pre><pre style="background:white"><tt><span style="color:black">dip/blow relationship.  I agree that the formula is confusing but I don't</span></tt></pre><pre style="background:white"><tt><span style="color:black">think it has to be.  Determining when let-off and aftertouch actually start</span></tt></pre><pre style="background:white"><tt><span style="color:black">seems to be the problem.  Once established, however, I see no reason why a</span></tt></pre><pre style="background:white"><tt><span style="color:black">default setting for the sake of this formula can't be used.  Moreover, I</span></tt></pre><pre style="background:white"><tt><span style="color:black">find that it's the aftertouch part that is confusing.  As far as the formula</span></tt></pre><pre style="background:white"><tt><span style="color:black">goes, my own experience suggests that a let-off number of 1.5 and an</span></tt></pre><pre style="background:white"><tt><span style="color:black">aftertouch number of 2.5 produces regulation specs that I expect to find</span></tt></pre><pre style="background:white"><tt><span style="color:black">with a given action ratio.  The problem seems to be defining exactly what</span></tt></pre><pre style="background:white"><tt><span style="color:black">aftertouch is, at least as it pertains to this formula.  Blow, dip and</span></tt></pre><pre style="background:white"><tt><span style="color:black">let-off are more easily defined.   </span></tt></pre><pre style="background:white"><tt><span style="color:black"> </span></tt></pre><pre style="background:white"><tt><span style="color:black">David Love</span></tt></pre><pre style="background:white"><tt><span style="color:black"><a target="_blank" href="http://www.davidlovepianos.com">www.davidlovepianos.com</a></span></tt></pre><pre style="background:white"><tt><span style="color:black"> </span></tt></pre><pre style="background:white"><tt><span style="color:black"> </span></tt></pre><pre style="background:white"><tt><span style="color:black">-----Original Message-----</span></tt></pre><pre style="background:white"><tt><span style="color:black">From: <a href="mailto:pianotech-bounces@ptg.org">pianotech-bounces@ptg.org</a> [<a href="mailto:pianotech-bounces@ptg.org?">mailto:pianotech-bounces@ptg.org</a>] On Behalf</span></tt></pre><pre style="background:white"><tt><span style="color:black">Of Jim Ialeggio</span></tt></pre><pre style="background:white"><tt><span style="color:black">Sent: Sunday, August 26, 2012 8:32 AM</span></tt></pre><pre style="background:white"><tt><span style="color:black">To: <a href="mailto:pianotech@ptg.org">pianotech@ptg.org</a></span></tt></pre><pre style="background:white"><tt><span style="color:black">Subject: [pianotech] action ratio</span></tt></pre><pre style="background:white"><tt><span style="color:black"> </span></tt></pre><pre style="background:white"><tt><span style="color:black">David L said:</span></tt></pre><pre style="background:white"><tt><span style="color:black"> </span></tt></pre><pre style="background:white"><tt><span style="color:black"><The question at hand has to do with what exactly is the after touch spec</span></tt></pre><pre style="background:white"><tt><span style="color:black">that's used to make the formula ratio by product of the levers equal to the</span></tt></pre><pre style="background:white"><tt><span style="color:black">blow/dip ratio as given.</span></tt></pre><pre style="background:white"><tt><span style="color:black">(and)</span></tt></pre><pre style="background:white"><tt><span style="color:black"><But when I input those numbers in this calculator, as you can see, then by</span></tt></pre><pre style="background:white"><tt><span style="color:black">that formula a 5.75 AR with 45 mm of blow distance should regulate with 8.6</span></tt></pre><pre style="background:white"><tt><span style="color:black">mm of dip.</span></tt></pre><pre style="background:white"><tt><span style="color:black"> </span></tt></pre><pre style="background:white"><tt><span style="color:black">This illustrates the confusion I find in these formulas, if they are to be</span></tt></pre><pre style="background:white"><tt><span style="color:black">used from a design perspective rather than as a ballpark reactive position</span></tt></pre><pre style="background:white"><tt><span style="color:black">in the field. I feel the (blow distance-let off)/key</span></tt></pre><pre style="background:white"><tt><span style="color:black">dip-aftertouch) part of the equation, when compared to the lever arms part</span></tt></pre><pre style="background:white"><tt><span style="color:black">of the equation is apples to oranges.</span></tt></pre><pre style="background:white"><tt><span style="color:black"> </span></tt></pre><pre style="background:white"><tt><span style="color:black">The lever arm side of the equation looks at the lever arms as the product of</span></tt></pre><pre style="background:white"><tt><span style="color:black">fixed ratios.  However, the blow distance ratio does not look at blow</span></tt></pre><pre style="background:white"><tt><span style="color:black">distance and key dip as fixed ratios, but rather inputs arbitrary</span></tt></pre><pre style="background:white"><tt><span style="color:black">letoff/aftertouch as necessary to make that side of the equation match the</span></tt></pre><pre style="background:white"><tt><span style="color:black">fixed ratio side, as I think you've noted, David.  Or seen another way, if</span></tt></pre><pre style="background:white"><tt><span style="color:black">you are going to use the blow distance side of the equation as given, then</span></tt></pre><pre style="background:white"><tt><span style="color:black">the lever arm side must take into consideration the whip's changing leverage</span></tt></pre><pre style="background:white"><tt><span style="color:black">and the shank's changing leverage during letoff. This changing leverage</span></tt></pre><pre style="background:white"><tt><span style="color:black">presents difficulties that would require computing complexities way beyond</span></tt></pre><pre style="background:white"><tt><span style="color:black">simple algebra.</span></tt></pre><pre style="background:white"><tt><span style="color:black"> </span></tt></pre><pre style="background:white"><tt><span style="color:black">Taken in this light, your shy 8.6mm dip could be more a result of blow being</span></tt></pre><pre style="background:white"><tt><span style="color:black">quantified artificially.  According to the fixed leverages, blow is not the</span></tt></pre><pre style="background:white"><tt><span style="color:black">distance between hammer at rest and the strings minus letoff, but rather</span></tt></pre><pre style="background:white"><tt><span style="color:black">(Full unimpeded travel of the hammer with out any letoff or</span></tt></pre><pre style="background:white"><tt><span style="color:black">strings) = Action ratio*(key dip-aftertouch).</span></tt></pre><pre style="background:white"><tt><span style="color:black"> </span></tt></pre><pre style="background:white"><tt><span style="color:black">By the way, my comment here is not that this formula doesn't empirically</span></tt></pre><pre style="background:white"><tt><span style="color:black">work, but rather that the thinking behind it seems to be selective and thus</span></tt></pre><pre style="background:white"><tt><span style="color:black">confusing, at least to me.</span></tt></pre><pre style="background:white"><tt><span style="color:black"> </span></tt></pre><pre style="background:white"><tt><span style="color:black">Jim Ialeggio</span></tt></pre><pre style="background:white"><tt><span style="color:black"> </span></tt></pre><pre style="background:white"><tt><span style="color:black"> </span></tt></pre><pre style="background:white"><tt><span style="color:black"> </span></tt></pre><pre style="background:white"><tt><span style="color:black"> </span></tt></pre><pre style="background:white"><tt><span style="color:black">-- </span></tt></pre><pre style="background:white"><tt><span style="color:black">Jim Ialeggio   </span></tt></pre><pre style="background:white"><tt><span style="color:black"><a href="mailto:jim@grandpianosolutions.com">jim@grandpianosolutions.com</a></span></tt></pre><pre style="background:white"><tt><span style="color:black">978 425-9026</span></tt></pre><pre style="background:white"><tt><span style="color:black">Shirley Center, MA</span></tt></pre><pre style="background:white"><tt><span style="color:black"> </span></tt></pre></div> </div> </div> </div> </div>  </div> </font>