Ron, Haven't tried the Protex, but Kent Webb from Steinway said the same thing in Atlanta. Also suggested that it's more productive to just bring up to pitch and settle in, rather than bringing the note over pitch. Chuck Raynor Beaufort, SC pianotech-request at ptg.org wrote: > Send Pianotech mailing list submissions to > pianotech at ptg.org > > To subscribe or unsubscribe via the World Wide Web, visit > https://www.moypiano.com/resources/#archives > or, via email, send a message with subject or body 'help' to > pianotech-request at ptg.org > > You can reach the person managing the list at > pianotech-owner at ptg.org > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Pianotech digest..." > > ------------------------------------------------------------------------ > > Today's Topics: > > 1. Soundboard drydown for installation (Richard Brekne) > 2. floccinaucinihilipilification of a piano (David Nereson) > 3. Soundboard drydown for installation (Richard Brekne) > 4. Re: Charge more to tune a Steinway? (David Nereson) > 5. Damppchaser installation on Yamaha (Tom Driscoll) > 6. Re: Soundboard installation, next topic : the glue (John Delacour) > 7. Re: Soundboard installation, next topic : the glue (Ron Nossaman) > 8. Soundboard installation, next topic : the glue (Richard Brekne) > 9. Re: Soundboard installation, next topic : the glue > (mccleskey112 at bellsouth.net) > 10. Soundboard installation, next topic : the glue (Richard Brekne) > 11. tuning Steinway uprights (Ronny Boyd) > 12. RE: Titebond Liquid Hide Glue specs...was the glue > (St?phane Collin) > 13. Re: Charge more to tune a Steinway? (Phil Bondi) > 14. Re: Soundboard contruction methods (John Delacour) > > > ------------------------------------------------------------------------ > > Subject: > Soundboard drydown for installation > From: > Richard Brekne <ricb at pianostemmer.no> > Date: > Wed, 23 Jan 2008 22:08:25 +0100 > To: > pianotech at ptg.org > > To: > pianotech at ptg.org > > > I tend to agree Jude. That said... seems pretty clear to me that Rons > experiment shows rather conclusively at least three things. One, that > the immediate reaction of the soundboard to downbearing is for the > edges to pull away from the rim. Two, that the soundboard taking on > humidity will attempt to grow outwards above the center line of the > assembly... and a tight fitting rim will resist the thing crowning > .... not aid. Three that the edge wood of an assembly is considerably > stronger then has been loosely suggested many a time on this list. > > I still think the whole thing functions more like a cable supported > arch then anything else. The ribs do indeed experience tension as the > panel takes on humidity. Both from bending and no doubt some small > amount of absolute tension. That is to say the entire rib will be > more lean more towards the tension side of the balance between tension > and compression then a similar rib that is simply bent would. The > more you compress the board either by increasing downbearing or by > letting the assembly take on humidity... the more tense the <<cable>> > becomes. That will continue until such point as the panel itself > experiences compression failure. > > Cheers > RicB > > > > > The only purpose of that model was to illustrate that > > soundboard crown isn't an end buttressed arch, which I think > > it did well enough. What else would you expect or wish a > > larger and more complex model to show? > > > I guess I'm not thinking about a different model but rather a > different experiment. I'll get back to you when I finally pose a > real question. :) > > Jude Reveley, RPT > Absolute Piano Restoration, LLC > Lowell, Massachusetts > (978) 323-4545 > > > > ------------------------------------------------------------------------ > > Subject: > floccinaucinihilipilification of a piano > From: > "David Nereson" <dnereson at 4dv.net> > Date: > Wed, 23 Jan 2008 13:54:24 -0700 > To: > "Pianotech List" <pianotech at ptg.org> > > To: > "Pianotech List" <pianotech at ptg.org> > > > Next time you feel bad about charging money to "condemn" a piano, > i.e., letting the owner know that it should be junked or just isn't > worth putting any money into, you could perhaps call it by this more > hi-falutin' name. (See subject line; I'm not going to type it again). > --David Nereson, RPT > > > ------------------------------------------------------------------------ > > Subject: > Soundboard drydown for installation > From: > Richard Brekne <ricb at pianostemmer.no> > Date: > Wed, 23 Jan 2008 22:28:39 +0100 > To: > pianotech at ptg.org > > To: > pianotech at ptg.org > > > This is a point that has had me scratching my head for a long time. > Strikes me that a board that is dried to 4 % MC before ribbing will > simply return to this state at any time in the pianos life the MC gets > back to that level. It will simply flatten out... and their will be > no compression stress in the assembly. If string downbearing is > appropriately set to begin with.. there will be no downbearing > either. Whats the problem ? > > If on the other hand a board is simply dried to 6.5 % MC... then > ribbed.... regardless of what kind of ribs one uses, if it reaches 4 % > MC at some point in the future then THIS is the board that should > worry about reverse crown... splitting apart... or worse. What am I > missing here ? > > Cheers > RicB > > > Oh, and a practical question about your being in the CC > capital of the universe. When the RH% gets into the low teens, > say 15%, the MC of the soundboards will be 3.5%, at or before > which point a CC board will be flat or have reverse crowned. > Do you have a recognized annual killer octave season or > festival there? > > > > ------------------------------------------------------------------------ > > Subject: > Re: Charge more to tune a Steinway? > From: > "David Nereson" <dnereson at 4dv.net> > Date: > Wed, 23 Jan 2008 14:35:39 -0700 > To: > "Pianotech List" <pianotech at ptg.org> > > To: > "Pianotech List" <pianotech at ptg.org> > > > > > > > Greetings, > > Does anyone else out there feel that you need more time > to tune Steinways? Is it just me or what? I am thinking of > charging alittle more to tune them. I have been tuning for 5 years. > > Julia Gottshall, > Reading, PA > > > I assume you want to charge more because they take longer. If > Steinways take longer, then so should any other piano with no > tuning pin bushings. And if we charge more for pianos that take > longer, then we'd also have to charge more for: > -Korean and Chinese pianos, because they need so much in the way > of aligning hammers to strings and spacing unisons in order to get > the hammers to hit all the strings so they can be tuned > -Baldwins, especially newer ones, because of having to wrestle > with tight tuning pins > -brand new pianos, or those just a few years old, again because of > tight tuning pins that are hard to set > -full uprights, because one has to stand the whole time > -any piano with loose tuning pins, because it takes extra time to > set them or drive/replace them > -certain Wurlitzer spinets, because they're so inaccessible and > case parts have to be removed just to get at the tuning pins > -any piano that takes longer because the strings don't render > easily through the bridges/pressure bar/capo and you have to > wrestle more to set pins. > etc. etc. > Do you plan on charging more for Steinways but not Boesendorfers > and other high-end makes? > --David Nereson, RPT > > > > > > > ------------------------------------------------------------------------ > > Subject: > Damppchaser installation on Yamaha > From: > "Tom Driscoll" <tomtuner at verizon.net> > Date: > Wed, 23 Jan 2008 16:50:27 -0500 > To: > "Pianotech List" <pianotech at ptg.org> > > To: > "Pianotech List" <pianotech at ptg.org> > > > >> Conrad, >> >> But can you blame that on the country of origin? The only piano I've >> ever had to do that to (in my admittedly limited experience) was a >> Yamaha U1. Do you actually carve out the bottom of the keybed, or the >> top of the panel? >> >> Mike >> >> Mike , > The word "carve" conjures up an image of a guy with a chainsaw! > I've installed dozens of systems in the U series Yamaha verticals > --Well maybe one dozen. > I cut a V shaped notch with a fine fret saw then round out the > bottom of the "V" with a rat tail file-rasp on the top -middle of the > lower front panel. Two minutes tops. > This is entirely unnoticable and I never ask permission . > Tom Driscoll > > > > > ------------------------------------------------------------------------ > > Subject: > Re: Soundboard installation, next topic : the glue > From: > John Delacour <JD at Pianomaker.co.uk> > Date: > Wed, 23 Jan 2008 21:56:42 +0000 > To: > Pianotech List <pianotech at ptg.org> > > To: > Pianotech List <pianotech at ptg.org> > > > At 14:20 -0600 23/1/08, Ron Nossaman wrote: > >> The definitions as used for the last five years or so on list are: > > Thank you for the concise explanation. I know that the terms have > been commonly used on the list but that doesn't mean it's easy to find > any place in the archives where they are clearly explained and compared. > >> CC=compression crowned, consisting of flat ribs with panel >> compression forming and supporting crown under both string >> downbearing and the ribs' attempt to naturally straighten back out. >> Steinway US, Steingraeber, and Sauter build boards this way. > > And yet Hartwig of Steinway Hamburg is reported to say "and yes the > ribs are slightly curved prior to gluing them onto the board." > Depending on what he means by "slightly", surely that could mean a > Steinway board is more or less "rib-crowned" by your terminology? > >> RC=rib crowned, consisting of ribs with a crown machined directly >> into them,.. > > Would that be the same,in effect, as saying planed to a convex curve > on the upper side? > >> ..and supplying positive beam support to crown under downbearing in >> addition to the support supplied by panel compression. > > This compression being created by the force produced by the summer > growth (mainly) of the spruce trying to expand after being glued to > the ribs in a more or less dehydrated condition. Is that what you're > saying? It seems to be, but anyone reading your description without > much knowledge might easily ask "what compression?!" > >> This is the most common construction method among today's >> manufacturers. > > And has been a common construction method for well over 120 years, is > that not so? > >> RC&S=rib crowned and supported, consisting of ribs with a crown >> machined directly into them, sized and numbered sufficiently to >> support crown under downbearing load without the aid of panel >> compression. To my knowledge, Walter is the only manufacturer >> building boards this way, though there are a number of small shops >> doing this now, with considerable success. > > Do you count yourself among that number? If I understand this > correctly in the context of the other two methods and by contrast with > them, then when the board is glued to the ribs, presumably without any > previous special dehydration, the curvature resulting in the board > will lead to some tension in the board and when the piano is strung > and the curvature of the board diminishes this tension will diminish > and leave the board in roughly a state unstressed either by tension or > by compression. Is that, broadly speaking, the intention? > >> And no, 15' isn't an excessively tight radius for a machine crowned >> rib. I go down to 4 meter in the treble > > That's another matter. 15 ft. was not mentioned as the radius of a > crowned rib but as the radius of the installed board in my picture > >> Whatever Wolfenden has to say about it. > > He has not much to say about it. > > JD > > > > > ------------------------------------------------------------------------ > > Subject: > Re: Soundboard installation, next topic : the glue > From: > Ron Nossaman <rnossaman at cox.net> > Date: > Wed, 23 Jan 2008 16:43:27 -0600 > To: > Pianotech List <pianotech at ptg.org> > > To: > Pianotech List <pianotech at ptg.org> > > > >>> CC=compression crowned, consisting of flat ribs with panel >>> compression forming and supporting crown under both string >>> downbearing and the ribs' attempt to naturally straighten back out. >>> Steinway US, Steingraeber, and Sauter build boards this way. >> >> And yet Hartwig of Steinway Hamburg is reported to say "and yes the >> ribs are slightly curved prior to gluing them onto the board." >> Depending on what he means by "slightly", surely that could mean a >> Steinway board is more or less "rib-crowned" by your terminology? > > I said Steinway US, as in NY. They have always used flat ribs, and by > all indication always will. The Hamburg product is considerably > different. An eternal source of confusion also comes from the always > vague wording concerning "curved" ribs. If the curve is cut into the > rib, yes, it's rib crowned. If the curve is bent into the rib, no, > it's compression crowned. Which is the case here? > > >>> RC=rib crowned, consisting of ribs with a crown machined directly >>> into them,.. >> >> Would that be the same,in effect, as saying planed to a convex curve >> on the upper side? > > Correct. > > >>> ..and supplying positive beam support to crown under downbearing in >>> addition to the support supplied by panel compression. >> >> This compression being created by the force produced by the summer >> growth (mainly) of the spruce trying to expand after being glued to >> the ribs in a more or less dehydrated condition. Is that what you're >> saying? It seems to be, but anyone reading your description without >> much knowledge might easily ask "what compression?!" > > Yes. Panel compression is also commonly achieved or increased by > pressing the assembly into a curved caul as the ribs are glued on. > > >>> This is the most common construction method among today's >>> manufacturers. >> >> And has been a common construction method for well over 120 years, is >> that not so? > > Yes, it has. > > >>> RC&S=rib crowned and supported, consisting of ribs with a crown >>> machined directly into them, sized and numbered sufficiently to >>> support crown under downbearing load without the aid of panel >>> compression. To my knowledge, Walter is the only manufacturer >>> building boards this way, though there are a number of small shops >>> doing this now, with considerable success. >> >> Do you count yourself among that number? > > Yes. My crowned rib sets would support full string downbearing without > the panel being present. > > >> If I understand this correctly in the context of the other two >> methods and by contrast with them, then when the board is glued to >> the ribs, presumably without any previous special dehydration, the >> curvature resulting in the board will lead to some tension in the >> board and when the piano is strung and the curvature of the board >> diminishes this tension will diminish and leave the board in roughly >> a state unstressed either by tension or by compression. Is that, >> broadly speaking, the intention? > > I dry panels to 6%MC, so depending on where the piano goes, there will > often be some compression in the panel. The difference is that the > RC&S assembly doesn't need panel compression to maintain stiffness and > crown under bearing load, where the CC and RC do. > > Ron N > > > ------------------------------------------------------------------------ > > Subject: > Soundboard installation, next topic : the glue > From: > Richard Brekne <ricb at pianostemmer.no> > Date: > Wed, 23 Jan 2008 23:47:19 +0100 > To: > pianotech at ptg.org > > To: > pianotech at ptg.org > > > Hi you two.. and others > > What Hartwig has to say is about Hamburg instruments. He does not > speak for the NY instruments. I have an email exchange from John > Patton of NY Steinway asking the same questions about the NY variant > but I can not locate them right yet. I seem to remember tho that he > said they used curved ribs as well... tho I am not 100 % certain. I > posted twice about it on the list so ya'll can hunt this down in the > archives. > > I think the main points about these boards (on this list) comes down > to their viability and the ease of which they are constructed to the > intent of the builder / rebuilder. IMHO the whole shamilsh about CC, > or significantly compressed boards self destructing is simply grossly > overstated. Tho I have never experienced living in a place like > southern Iowa where humidity in the summer can feel like you are > living in a virtual sweat bath for three months. As for ease of > building... well to each their own. > I think also it goes without saying that all three types mentioned can > be very successfully employed to build very fine sounding > instruments. You all can argue all you want about what does and doesnt > sound good. I find that the world of pianists is so unbelievably > varied on the subject matter that all such arguement is basically > meaningless. > > Cheers RicB > > > >CC=compression crowned, consisting of flat ribs with panel > >compression forming and supporting crown under both string > >downbearing and the ribs' attempt to naturally straighten back > out. > >Steinway US, Steingraeber, and Sauter build boards this way. > > > And yet Hartwig of Steinway Hamburg is reported to say "and yes the > ribs are slightly curved prior to gluing them onto the board." > Depending on what he means by "slightly", surely that could mean a > Steinway board is more or less "rib-crowned" by your terminology? > > > > ------------------------------------------------------------------------ > > Subject: > Re: Soundboard installation, next topic : the glue > From: > <mccleskey112 at bellsouth.net> > Date: > Wed, 23 Jan 2008 16:45:37 -0600 > To: > "Pianotech List" <pianotech at ptg.org> > > To: > "Pianotech List" <pianotech at ptg.org> > > > Thanks John, I needed that. > Gerald mcCleskey RPT > Shreveport, LA > > ----- Original Message ----- From: "John Delacour" <JD at Pianomaker.co.uk> > To: "Pianotech List" <pianotech at ptg.org> > Sent: Wednesday, January 23, 2008 3:56 PM > Subject: Re: Soundboard installation, next topic : the glue > > >> At 14:20 -0600 23/1/08, Ron Nossaman wrote: >> >>> The definitions as used for the last five years or so on list are: >> >> Thank you for the concise explanation. I know that the terms have >> been commonly used on the list but that doesn't mean it's easy to >> find any place in the archives where they are clearly explained and >> compared. >> >>> CC=compression crowned, consisting of flat ribs with panel >>> compression forming and supporting crown under both string >>> downbearing and the ribs' attempt to naturally straighten back out. >>> Steinway US, Steingraeber, and Sauter build boards this way. >> >> And yet Hartwig of Steinway Hamburg is reported to say "and yes the >> ribs are slightly curved prior to gluing them onto the board." >> Depending on what he means by "slightly", surely that could mean a >> Steinway board is more or less "rib-crowned" by your terminology? >> >>> RC=rib crowned, consisting of ribs with a crown machined directly >>> into them,.. >> >> Would that be the same,in effect, as saying planed to a convex curve >> on the upper side? >> >>> ..and supplying positive beam support to crown under downbearing in >>> addition to the support supplied by panel compression. >> >> This compression being created by the force produced by the summer >> growth (mainly) of the spruce trying to expand after being glued to >> the ribs in a more or less dehydrated condition. Is that what you're >> saying? It seems to be, but anyone reading your description without >> much knowledge might easily ask "what compression?!" >> >>> This is the most common construction method among today's >>> manufacturers. >> >> And has been a common construction method for well over 120 years, is >> that not so? >> >>> RC&S=rib crowned and supported, consisting of ribs with a crown >>> machined directly into them, sized and numbered sufficiently to >>> support crown under downbearing load without the aid of panel >>> compression. To my knowledge, Walter is the only manufacturer >>> building boards this way, though there are a number of small shops >>> doing this now, with considerable success. >> >> Do you count yourself among that number? If I understand this >> correctly in the context of the other two methods and by contrast >> with them, then when the board is glued to the ribs, presumably >> without any previous special dehydration, the curvature resulting in >> the board will lead to some tension in the board and when the piano >> is strung and the curvature of the board diminishes this tension will >> diminish and leave the board in roughly a state unstressed either by >> tension or by compression. Is that, broadly speaking, the intention? >> >>> And no, 15' isn't an excessively tight radius for a machine crowned >>> rib. I go down to 4 meter in the treble >> >> That's another matter. 15 ft. was not mentioned as the radius of a >> crowned rib but as the radius of the installed board in my picture >> >>> Whatever Wolfenden has to say about it. >> >> He has not much to say about it. >> >> JD >> >> >> >> -- >> ______________________________________________________________________ >> Delacour Pianos * Silo * Deverel Farm * Milborne St. Andrew >> Dorset DT11 0HX * England >> Phone: +44 1202 731031 >> Mobile: +44 7801 310 689 * Fax: +44 870 705 3241 >> ______________________________________________________________________ > > > > ------------------------------------------------------------------------ > > Subject: > Soundboard installation, next topic : the glue > From: > Richard Brekne <ricb at pianostemmer.no> > Date: > Wed, 23 Jan 2008 23:58:35 +0100 > To: > pianotech at ptg.org > > To: > pianotech at ptg.org > > > Hi all... I just had a look in the archives and found the post I was > looking for about NY Steinway ribs. I must correct my last post where > I thought I remembered John Patton saying they used crowned ribs... > they are flat in NY. > > And since the word "curved" seems to present some ambiguity for > some... when I visit Hamburg I will re-state the question in such a > way so as to not allow for any confusion on the matter at all. It > didnt present any problem for John I might add. I asked if they were > curved... he said they were flat. > > In any case... the scoop on NY Steinways is just below... direct from > John Patton. > > Cheers > RicB > > > > Hi Richard. > > > > ..........The ribs are flat and pressed into a curved caul. > However, the > > panel is > > dried to 5.5%. Hope > > that clears it up. > > > > Best regards, John > > > > -----Original Message----- > > From: Richard Brekne [mailto:rbrekne at broadpark.no] > > Sent: Tuesday, September 30, 2003 9:38 AM > > To: Patton, John > > Subject: Re: Steinway Ribs > > > > Hi John > > > > Been a while since I last wrote you. I trust you are well. > > > > I wonder if you could confirm for me the official line on > > how Steinway crowns its boards. I am under the understanding > > that the use curved ribs, panel dried out to less then 5% > > emc, and pressed into a curved caul. I keep getting > > conflicting stories about the ribs... either they are flat > > or machine curved... which is it ? > > > > FWIW > > > > Cheers > > RicB > > > > ------------------------------------------------------------------------ > > Subject: > tuning Steinway uprights > From: > Ronny Boyd <ronnybyd at yahoo.com> > Date: > Wed, 23 Jan 2008 15:02:55 -0800 (PST) > To: > pianotech at ptg.org > > To: > pianotech at ptg.org > > > *At a recent guild meeting with a Steinway rep. The question was > asked, "why is it so hard to tune the upper treble on a Steinway?" His > answer was to use Protex Prolube on the felt that is just above the > "V" bar. He didn't know why it worked but it did. So the next time I > tuned a Steinway upright I used the Prolube and by God! It workes!! > Don't ask me to give an explanation as to why it works but it does. > Has anybody else tried this? * > ** > *Ron Boyd - Milwaukee Guild* > ** > > ------------------------------------------------------------------------ > > Subject: > RE: Titebond Liquid Hide Glue specs...was the glue > From: > Stéphane Collin <collin.s at skynet.be> > Date: > Thu, 24 Jan 2008 00:11:27 +0100 > To: > "'Pianotech List'" <pianotech at ptg.org> > > To: > "'Pianotech List'" <pianotech at ptg.org> > > > Hi Terry. > > > > You said : > > So now for the practical question: So HOW MUCH does liquid hide glue > soften with high humidity? Enough for it to be a concern using it for > the soundboard/rim joint? Is hot hide glue similarly affected by > humidity? If so, then I would say there is little concern with liquid > hide glue softening with high humidity. > > > > > > That is exactly how I am thinking now about this. > > I did try a liquid hide glue joint of spruce scrap on hard wood scrap, > and put it in my bathroom, where the humidity is about 54 % now. I > must say that even after 36 hours, the excess glue is still not dry, > that is, it is soft and you can indent it with your thumb nail. That > being said, the joint is very strong : no way I can make the bond > fail. Some comments tended to say this is a preferable condition > (little creeping allowed). > > Anyway, if I hear you and Dale say there is full satisfaction in your > areas where climate is comparable to mine, I tend to not hesitate and > go for this. > > > > It is late now, but tomorrow I will post the specs of Ciresa that I > just received, for you all to appreciate. > > > > Best regards. > > > > Stéphane Collin. > > > ------------------------------------------------------------------------ > > Subject: > Re: Charge more to tune a Steinway? > From: > Phil Bondi <phil at philbondi.com> > Date: > Wed, 23 Jan 2008 18:52:51 -0500 > To: > Pianotech List <pianotech at ptg.org> > > To: > Pianotech List <pianotech at ptg.org> > > > > itunepiano at aol.com wrote: > I tune it once per year, not 4 times per year as >> I'm budgeted for. > > Is this the definition of tuning by rumor? > > -rn > > > > ------------------------------------------------------------------------ > > Subject: > Re: Soundboard contruction methods > From: > John Delacour <JD at Pianomaker.co.uk> > Date: > Thu, 24 Jan 2008 00:01:59 +0000 > To: > Pianotech List <pianotech at ptg.org> > > To: > Pianotech List <pianotech at ptg.org> > > > Time for a change of subject heading, I think : > > > At 16:43 -0600 23/1/08, Ron Nossaman wrote: > >> I said Steinway US, as in NY. They have always used flat ribs, and by >> all indication always will. The Hamburg product is considerably >> different. An eternal source of confusion also comes from the always >> vague wording concerning "curved" ribs. If the curve is cut into the >> rib, yes, it's rib crowned. If the curve is bent into the rib, no, >> it's compression crowned. Which is the case here? > > I don't know how you would "bend a curve" into a rib except by > steaming it and thus straining the structure and I can't imagine > anyone going about it that way, so I have little doubt that Hamburgs > ribs are planed to a crown just as most people's if Hartwig is to be > taken at his word. > >>>> ..and supplying positive beam support to crown under downbearing in >>>> addition to the support supplied by panel compression. >>> >>> This compression being created by the force produced by the summer >>> growth (mainly) of the spruce trying to expand after being glued to >>> the ribs in a more or less dehydrated condition. Is that what >>> you're saying? It seems to be, but anyone reading your description >>> without much knowledge might easily ask "what compression?!" >> >> Yes. Panel compression is also commonly achieved or increased by >> pressing the assembly into a curved caul as the ribs are glued on. > > Well, that is not the compression that is most significant! The > dished table is just a device to facilitate close contact of the ribs > with the board while gluing. Of course some compression of the fibres > will result at the dished side but at the same time some tension, or > stretching of the fibres, will result on the under-side. The > significant and more telling compression results as the board > re-hydrates, at which time the temporary tension introduced by the > slight bending is negated and quickly changed into compression, which > compression is further increased as the down-bearing of the strings > comes into effect. > > Now to use the local neologism of "rib-crowned" for such an assembly, > no matter how it may have caught on, strikes me as either misleading > or just plain meaningless. The term suggests that the board is > crowned by the ribs, which is not the case at all, and the contrasting > of "RC" with "CC" leads one to suppose that compression is not present > in a "rib-crowned" board, when in fact compression is the principal > factor in the development and maintenance of the crown and the > crowning of the ribs is carried out simply to prevent the ribs from > straining to pull down the naturally-formed crown to no purpose. > >> Yes. My crowned rib sets would support full string downbearing >> without the panel being present. > > How would they sound? :-) > >> I dry panels to 6%MC, so depending on where the piano goes, there >> will often be some compression in the panel. The difference is that >> the RC&S assembly doesn't need panel compression to maintain >> stiffness and crown under bearing load, where the CC and RC do. > > I understand. Now, while my own personal hobby-horse is that all that > matters in a soundboard is the ratio of stiffness to mass; given the > very imperfect aeolotropic nature of spruce and other woods and the > need to make it behave and provide as much stiffness or resilience as > possible across the grain, compression strikes me, and has struck > countless others down the generations, as a very useful aid. Terry > Farrell mentioned recently the behaviour of a certain make of piano > whose soundboard has neither crown nor compression: > > At 06:51 -0500 26/11/07, Farrell wrote: > >> Have you ever listened to a Xxx? Maybe some would want to call what >> they have "power", but the pianos distort badly at any medium-lound >> volume. > > My answer to that is first: yes, I have, at the inauguration of one of > them at a hall in Wales. My first impression during the concert was > that it sounded rather like a very old Bechstein, and a friend oan > colleague who was with me agreed. Afterwards we went on stage and I > was invited by the maker to try the piano. After playing it > sensitively for a few moments I decided to test the impression I had > that it would break down under heavy playing and hit it for all it was > worth. The effect was catastrophic. I might as well have kicked a > pile of tin cans. > > That is not to say that either compression or crown are necessary for > a good soundboard -- but for a board without either, spruce is not the > right stuff. > > JD > > > > > > > > > > > ------------------------------------------------------------------------ > > _______________________________________________ > Pianotech list info https://www.moypiano.com/resources/#archives
This PTG archive page provided courtesy of Moy Piano Service, LLC