<HTML>In a message dated 11/24/2002 8:00:55 PM Pacific= Standard Time, RNossaman@cox.net writes: <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT= : 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">Subj:Re: Belly rail crown - = Why??? Date:11/24/2002 8:00:55 PM Pacific Standard Time From:<A HREF="mailto:RNossaman@cox.net">RNossaman@cox.net</A> Reply-to:<A HREF="mailto:pianotech@ptg.org">pianotech@ptg.org</A> To:<A HREF="mailto:pianotech@ptg.org">pianotech@ptg.org</A> Sent from the Internet      Ron writes >>There's nothing wrong with beveled rims, but if you find no performa= nce >>advantage to beveling rims and are building a piano, you wouldn't be= too >>eager to spend the time to cut the bevel. >      Dale wrtes >    I agree but there has to be some surface cut anyway f= lat or beveled > and As we've discovered through lengthy discussions some things are <BR= > > easier than others to determine as to there actual performance benefit.= > Stwy's diaphragmatic sound board design is a case in point. Murky water= > perhaps but as I recall the treble edge rasten was raised to meet the <= BR> > edge of the board so as to eliminate a bending strain by so doing. The = > idea was that it freed up the board. Ron writes You've put a couple of boards in Steinways. Have you ever found the treble <= BR> edge rasten to meet the edge of the board in any of them without having to <= BR> force the board down some considerable distance?</BLOCKQUOTE>    &nbs= p;  </FONT= >  You know quite well there is some forcing= of the bass and treble corners to get them down but when the edges do conta= ct the rim the two surface areas are somewhere in the same relative plane an= d certainly more so than purely flat surface. Besides we were discussing per= formance benifits       Dale writes         What's = the proof?  Probably subjective ears but hey we all do a good deal </FO= NT> <BLOCKQUOTE TYPE=CITE styl= e="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PA= DDING-LEFT: 5px">of our authenticating that way I.e. improvements in raw ham= mers by >voicing, tonal improvements from new strings. In the case of the stwy <B= R> >experiment the same type of subjectivity was used. Even if they used sam= e >action in 2 different pianos the sound board wood is different, possibly= >e.m.c.s'. I believe there concessus was it was tonally better. I couldn'= t say. >You, Del or Ron O might have A different slant on these findings. I Bet = you Do. Ron writes Sure I do. They were making these subjective evaluations in exclusively compression crowned boards, in controlled conditions, over a very short period of time. That's a whole lot of limiting assumptions when you're looking for performance improvements in something that's supposed to last <B= R> as long as pianos are expected to. Here's an onion, a pound of hamburger, a = teaspoon of salt, and a can of chicken stock. Make bouillabaisse.<FON= T COLOR="#000000" style="BACKGROUND-COLOR: #ffffff" SIZE=2 FAMILY="= SANSSERIF" FACE="Arial" LANG="0"></BLOCKQUOTE>     &nbs= p;         Huh? <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT= : 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">     </FONT= ></BLOCKQUOTE>   Dale writes    At any rate the= best judge of that kind of subject determination in <BLOCKQUOTE TYPE=CITE styl= e="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PA= DDING-LEFT: 5px">my mind woud be the guys in the factory who were so familia= r with the old > design compared to the new one that there opinion would carry some real= weight Ron writes I've always had a problem with this thinking. When would the guys in the <BR= > factory working with the old ways ever get any experience with new ways to <= BR> refine their opinions? What you will most likely get here is "This is the <B= R> way we've always done it, so this way is best." And isn't that what we hear, for the most part?</BL= OCKQUOTE>    &nbs= p;   = Wow I totally disagree with you on this. To assumne that belly guys and fin= al voicers can't tell the difference from piano to piano especially over tim= e or have a valid opinion is a huge assumption or perhaps demeaning.<= FONT COLOR="#000080" style="BACKGROUND-COLOR: #ffffff" SIZE=3 FAMILY= ="SANSSERIF" FACE="Arial" LANG="0"> <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT= : 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">        Ron writes >>Why would you thin the board edges in the first place (except maybe = in the >>bass if you don't float it), and why would it be less desirable to u= nduly >>stress these edges than it would a thicker edge. >>Tail thinning from the corner,around behind the bass bridge and&nbsp= ; clear up >>through the curve but leaving the top treble end thicker as you well= know >>is fairly common practice in boards where tails aren't floated which=   is >>the majority of pianos that get restored in America.  My person= al >>experience is that thinning in these areas does provide a significan= t >>performance gain in sustain and clarity in conventionally >>reproduced  belly systems. Meaning In my case rib crowned board= s at 5 >>&1/2 to 6% emc Ron writes That's why I said "except in the bass if you don't float it". To many folks, thinning the panel edge means thinning the edge all around, which <BR= > won't do you any favors in the treble. Just looking for clarification.</FONT= ></BLOCKQUOTE>   <FO= NT COLOR="#000000" style="BACKGROUND-COLOR: #ffffff" SIZE=3 FAMILY= ="SERIF" FACE="Times New Roman" LANG="0">  I know first  rate rebuilders who thin= the curve, spine, bass corner and belly rail with exception of the high tre= ble corner. <FO= NT COLOR="#000080" style="BACKGROUND-COLOR: #ffffff" SIZE=3 FAMILY= ="SERIF" FACE="Times New Roman" LANG="0">Their sustain charachteristic= s are exceptional. Even a high treble can require some thinning depending on= your starting point.       Dale writes    &nbs= p;  I think it an impor= tant distinction to the readers on the list <BLOCKQUOTE TYPE=CITE styl= e="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PA= DDING-LEFT: 5px">   that particularly You and Del are using techni= ques that are, at least in > some cases, a radical departure from conventional belly replacement. Yo= ur > focus is completly on belly redesign which is great and many will > hopefully incorporate your ideas and find out if this a desirable > direction they wish to go. </BLOCKQUOTE>    &nbs= p;             <= /FONT>Ron writes <BLOCKQUOTE TYPE=CITE styl= e="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PA= DDING-LEFT: 5px">         Not so fas= t there. What you write about soundboard replacement indicates to me that yo= u are doing considerable re-design work yourself. You are thinning panels in the bass, but not in the treble. You are crowning ribs, <= BR> rather than compression crowning. You are laminating ribs. You are using <BR= > sugar pine in the bass and spruce in the treble. You are using tighter rib <= BR> radii than was originally evident in the bass (from compression crowning), <= BR> and multiple radii - considerably tighter in the treble than in the bass. <B= R> This doesn't sound an awful lot like accepting the subjectively arrived at <= BR> wisdom of the factory guys relying on the time honored old methods to me. <B= R> If any stress that can be avoided is undue stress, then any departure from <= BR> traditional designs and methods is radical. You is in that category too Albe= rt.</BLOCKQUOTE>      Ok ,first I didn't mean any offense if I = inadvertantly pushed a button but ,since I opened this can  Let me atte= mpt clarify "radical redesign" and "extra costs". I aslo have respect for th= e work you guys are doing and moreover your willingness to share it on list.= As I've told you before I've changed some methods and experimented with oth= ers due to the thoughts and ideas shared.       When I think of radical design I'm thinking o= f adding a sweeping bellyrail to every board design,( this is hard and time = consumning) reorienting the board grain angle,changing/calculating a new num= ber of ribs and consequently filling rib notches , cutting others and floati= ng every tail.  I've done some of this and it adds a fair bit of time b= oth in planning and execution. But so far I've eaten the cost of these items= mentioned to some degree in exchange for knowledge.  Laminated ribs ar= e quite time consumning and as a general practice I'm not doing it unless I = have convienent sized lumber to use. The rest I'll own ie. the rib crowning,= rib dimension changes and radii, less Panel compression and with the except= ion of an occasional tail float these don't add significantly in cost to a c= ompression crowned method but add significantly to the longevity factor of w= hich most, these days are convinced of an improvement.   I didn't ever say I was relying on the wisdom of the factory guys I j= ust didn't discount that they had an opinion and knew a thing or two.   I've drawn the distinction as clear as I can at least the way I think= of it. All the methods  and modifiactions are valid I'm just saying th= at at times were coming at it from slightly different directions which may b= e confusing to readers and those trying to bite off too much too soon as the= y start this journey. Yes Guilty of appling some modern (radical) techniques. Dale writes <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT= : 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">For some the tonal difference m= ay not be what satisfys them compared to >what is considered good to them. Ron writes Just as the tonal differences between traditional Steinway construction and = what you are doing may not be considered good to them. How can this be determined before the fact just by the construction method and design?</FONT= ></BLOCKQUOTE> It can't . the result= s have to speak for themselves . Did I hear an agreement there?  Sustain , power and clarity are the proof. Dale writes     </F= ONT>Also every one has to start som= ewhere. The redesign cost could be a <BLOCKQUOTE TYPE=CITE style="BORDER= -LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT:= 5px">significant impediment adding cost to an already pricey project.What's= the difference in your prices between reproducing a compression crowned Steinway board (as exactly as you can), and producing a board with <= BR> the design modifications you prefer?</BLOCKQUOTE>   Not that much          And incidentally, why do yo= u prefer <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MA= RGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">these design modificat= ions over the original      design?</BLOCKQUOTE>    &nbs= p;   Longevi= ty,power suatain and clarity=     &nbs= p;     Dale writes <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT= : 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">     &= nbsp; It would be good for us who have heard much about the superior > design traits in these hybrid board systems to actually experience it f= or > ourselves. As yet I've not heard anyone weigh in on this illusive > experience. Being a sustain freak myself I'd love to hear the improved = > sustain and color you both speak of. I've read comments on this list from folks who have heard examples of Del's = work. Haven't you? I did take my first radical re-design prototype to KC, <B= R> for a rebuilders' skills spot. It had some problems I've since learned to <B= R> avoid, but the killer octave and treble wasn't among them.</BLOCKQUOTE>    &nbs= p;   &n= bsp;  No I must have missed it. <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT= : 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px"> Go listen to Del's A. You're not that far away.</BLOCKQUOTE>   Good idea</FONT= > <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT= : 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px"> >>Isn't Floating a tail simply a removal bending strains and stiffness= es >>caused by panel restrictions due to a clamped edge system? It's a lot more than that. It's disconnecting the panel from the rim altogether.</BLOCKQUOTE>      My point exactlyWer= e saying the same thing here= <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT= : 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px"> >>How is a board stressed more by a rim beveled 1� less than the >>angle at which the rim meets the panel under load, than it is by a r= im >>beveled 1� more? Doesn't compute. >>        Ron N > > >      I think you misunderstood my thought. Or = maybe I did. The rim bevels > on stwys roughly equating  1 & 1/2 degrees will mate with a bo= ard in the > 60ft. crown range with no  load. What I was trying to say was&nbsp= ; that a > lesser board angle due to string load might more closely match the crow= n > of the board under load. Yes I see your point though. Yep, bent up, or bent down is still bent. >      It is however interesting as to how much = faux crown can be exhibited > in an old board only to have it disappear completly upon it's removal <= BR> > from the case. A condition or anomaly I attribute soley to the rim > bevel  capturing the rib ends and panel edge. It does have some ,a= lbeit, > small influence. Any way I don't dismiss it completly. >     Regards >      Dale Erwin That puts it in the realm of how much stress is undue stress. As you said, <= BR> it's faux crown. Regards, Ron N </BLOCKQUOTE> </HTML>