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Advice needed

  • 1.  Advice needed

    Posted 02-18-2020 03:46

    I recently tuned an old grand piano, approx 80 years old, for a new client. New tuning pins, steel wire and bass strings were installed in this piano about 4 years ago.

    The sound is constrained, some of the bass strings have gone dull and others are rattling and metallic sounding and many of the steel wire strings have metallic zinging and sizzling in the unisons.

    I have checked the crown, which is currently at 0 to 0. 5mm and downbearing which is about 3 to 4 degrees across the scale.

    The mechanism was also restored with new Abel hammerheads (not natural felt) installed too.

    All the work was neatly done but the grand has these problems.

    Any advice on what should/could be done  on this grand would be appreciated.

    Thank you.



    ------------------------------
    Mark Davis
    Piano Tuner/Technician
    ------------------------------


  • 2.  RE: Advice needed

    Posted 02-18-2020 06:03
    My thoughts on the matter,

    1. The downbearing needs to be reduced. Not sure exactly how to do that. Any advice on how to do this would be appreciated!
    2. The bass strings may not have turned when installed so hence the dullness and rattling and metallic zinging. So, they could be checked when addressing the excessive down bearing. If they have not been turned then I would turn them and once retensioned and tuned see if they have improved, if not I would need to quote for new bass strings. 
    3. The metallic sounds, sizzling and zinging may be hammer to string mating (I forgot to check this) wear in the agraffes and capo bar areas. 
    4. I am fine with hammer filling and hammer to string mating but have never addressed agraffe and capo bar string groove removal/filing. Not sure how difficult this is and how much time it would take and how to price for it?

    ------------------------------
    Mark Davis
    Piano Tuner/Technician
    ------------------------------



  • 3.  RE: Advice needed

    Posted 02-18-2020 08:18
    Advice...run for the nearest exit...its not your problem.

    3-4 deg, if your measurement is correct is off the charts. Without bridgework it is impossible, even with adjustable perimeter bolts, which this work surely did not include. That in addition to the potential agraffe sounds means restring, and recap, and not in the customer's house. You could experiment with the bass string windings, but this is such lousy work, why would you choose to own the mess.
    The action work, re the zinging is probably up to the same level of incompetence...your chance of resolving this, on a minor on-site budget is quite low.



    ------------------------------
    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 4.  RE: Advice needed

    Member
    Posted 02-18-2020 08:37
    Hello Mark,

    You haven't said anything about the size and/or make and value of the piano. I wonder if this piano is a case of where the owner should cut the losses and rather put the money toward a better instrument? It sounds rather like a bushel of trouble. For instance, is it a short piano with a short backscale length for the bass strings?

    You mention "some of the bass strings have gone dull", which suggests that at least some are not dull. In that case I think your primary issue for the bass tone quality (especially in view of the rattles) is the strings themselves. But you can test that quite readily by just picking one of the dull bass strings where you really have nothing to lose and see if changing the twist improves the situation. I have done that on some occasions and had success for some and for others not. In one instance it turned out that too much twist on the string had caused it to go dull; another time adding some twist brought them to life (which I can't now recall if it was a half turn or a full turn). You can test and gauge the amount of twist by clamping a small vise grip plier onto the loop section, loosen the string by turning the tuning pin just enough to allow you lift the loop off the hitch pin with the plier attached, then carefully allow the vise grip plier to rotate in the direction it wants to go while counting the turns (don't just release it, instead control the turning while allowing it to untwist). The amount of turns the string unwinds will give a clue what to do: if they come off with no twist then try adding a turn. If they come off indicating a significant turn amount then you may want to try reducing the turns.

    But in the case of rattling bass windings, I doubt you can do much about it. I suspect it's just a case of poor (read "cheap") set of bass strings.

    Re. the metallic sounding and zinging plain wire strings - you don't indicate if those are in the agraffe section or the v-bar section or both. If you suspect it's the agraffes themselves then you won't be able to do anything about without replacing strings, in which you can consider using this Walter Titex K1113-1.6 countersink bit to recondition them, available from MSC Direct (see <www.mscdirect.com>):
    Metric Radius Cut 60° Incl Angle High Speed Steel Combo Drill & Countersink 4mm Body Diam, 1.6mm Point Diam x 4.25mm Point Length, 35.5mm OAL, Right Hand Cut, Double End
    MSC Part #: 01032259, Mfr Part #: 5073546
    Bar code # 4031132158983
    Made in France

    But new agraffes might be a better bet?

    If the v-bar is grooved and source of the zinging, you can consider "machining" it to eliminate that source of false tone. Daniel Farrah in Canada has a good method for that, which you might want to explore.

    But, as I mentioned at the outset, consider if the value of the piano warrants any such effort. Unfortunately the previous work proved unsatisfactory, and can you guarantee repeating that work will produce good results? All the money spent on repairs both past and future would be a significant amount toward a better instrument.

    I could suggest an option for the bass bridge too, but the scope of this project sounds like it may be getting out of hand?


    ------------------------------
    Ernest Unrau
    Morden MB
    ------------------------------



  • 5.  RE: Advice needed

    Registered Piano Technician
    Posted 02-18-2020 09:22
    Someone else's poor work is not your problem. Please don't try to find band-aid solutions that will make it your problem. I don't care how much the owner paid for the work done 4 years ago. That is not your responsibility.

    ------------------------------
    Larry Messerly, RPT
    Bringing Harmony to Homes
    www.lacrossepianotuning.com
    ljmesserly@gmail.com
    928-899-7292
    ------------------------------



  • 6.  RE: Advice needed

    Member
    Posted 02-19-2020 12:12
    I agree with Larrys comments that someones poor work is not your problem . The thread showing a too high agraffe should be a red flag especially the added string height it causes and the gap going into the agraffe from the tuning pins. Not only that but it appears the plate was sprayed with the strings on since all of the strings and coils have gold overspray. Unfortunately we see some real hatchet jobs that the owner was led to believe it was a rebuild. A few years ago I looked at a Yamaha that was "rebuilt". The case was refinished and new bass strings installed. All of the plain steel strings where miss-strung since the triple unison was not looped around the first hitch pin and the mistake was not caught. Customer got hosed and "rebuilder" phone was no longer in service. NOTHING in the action was new either. I told the customer that there was nothing I could do and that the job was botched. They where too embarrassed to tell me who did the work or how much they paid.

    ------------------------------
    James Kelly
    Owner- Fur Elise Piano Service
    Pawleys Island SC
    843-325-4357
    ------------------------------



  • 7.  RE: Advice needed

    Registered Piano Technician
    Posted 02-18-2020 09:26
    Mark,

    One of the first questions out of my mouth would be: "Who did this work?"  Then I would contact them, or encourage the owner to do so, or be paid by the owner to investigate, the situation.  This usually leads to an understanding of WHY things are as they are. 

    As Jim indicated, if you are correct on the DB, this is a seriously whacked out situation. However, I have never been successful at diagnosing DB accurately with the piano in a strung state.

    From what you wrote I an envisioning wrong (too large) wire sizes yanked so tight they are burying themselves in the softer metal of agraffes and capo (which was probably not properly dressed either), and a host of other issues.

    If it turns out that an idiot (or inexperienced person) did this, then the best solution would be to rip it apart and do it all over again since idiocy (or inexperience) eventually shows up in every area (unexpectedly).  If it's not idiocy (or inexperience) and simply faulty materials that no one expected, well...maybe the same solution.  😢

    I feel the pain as I have seen this sort of thing before.

    Pwg

    ------------------------------
    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
    ------------------------------



  • 8.  RE: Advice needed

    Posted 02-18-2020 09:22
    Name the piano and post photos so we can see the quality of the work and bass strings.
    Is it possible that back scale duplex bars were omitted in restringing?

    ------------------------------
    Ed Sutton
    ed440@me.com
    (980) 254-7413
    ------------------------------



  • 9.  RE: Advice needed

    Registered Piano Technician
    Posted 02-18-2020 10:08
    Ed,

    Good point. I actually did that on the first SS I restrung because I had NOT de-strung it, and the duplex bars were gone when I got to it and in my inexperience at the time I didn't know any better.  Eventually fixed it by buying new ones and installing them appropriately. 

    Pwg

    ------------------------------
    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
    ------------------------------



  • 10.  RE: Advice needed

    Posted 02-18-2020 13:48
    Thanks to all for your replies. 
    I am not sure right now whether I should quote to do everything that is necessary or to just leave it alone. 

    I may be wrong with the downbearing figures. How is downbearing measured with accuracy?

    If the grand does have to much downbearing, what is the best way to correct this?

    ------------------------------
    Mark Davis
    Piano Tuner/Technician
    ------------------------------



  • 11.  RE: Advice needed

    Member
    Posted 02-18-2020 14:11
    Can't offer any ideas without more info as per items previously suggested by others, such as:
    1. What is the piano? (size, manufacturer, model, ser. #, etc.)
    2. How did you measure the crown? And/or how did you come up with the number(s) you stated?
    3. How did you measure the down bearing? And/or how did you come up with the values you stated?
    4. Did the piano originally have rear duplex bars and are those missing?
    5. Are the "zinging" sounds in the agraffe sections? V-bar sections? Both?
    6. Have you examined the condition of the v-bar sections using a mirror? Are there string grooves in the v-bar?
    7. Can you provide some photos?

    No one can offer concrete suggestions without at least that much info.


    ------------------------------
    Ernest Unrau
    Morden MB
    ------------------------------



  • 12.  RE: Advice needed

    Posted 02-18-2020 14:17
    It would be interesting to know the make of this piano.

    Peter G has made mention of duplex bars. It's been rare when I've
    tuned a Steinway to find the duplex sections properly tuned. On a big
    Kawai I tune they are so out of tune I've damped them out with felt.
    Sorry to ask a tangential question but what's the proper way of tuning
    the Duplexes?

    Best wishes

    David P

    --
    - - - - - - - - - - - - - - - - - - - - - - - -
    David Pinnegar, B.Sc., A.R.C.S.
    - - - - - - - - - - - - - - - - - - - - - - - -
    +44 1342 850594




  • 13.  RE: Advice needed

    Posted 02-18-2020 14:30
    I routinely correct bass d/b with aloquots. Sometimes half-rounds need to be used. I've cut/folded brass strips of varying thicknesses to insert under the wire but have now developed a better application. Brass tubing, flattened or with a strip of desired thickness of a brass strip squeezed inside the tubing. Looks better.  I simply lift the wire with a large screw driver or small pry bar and insert the bearing. A Lowell D/G gage helps.

    Many times there was way too much bearing on the low end and negative to nothing at the top. By decreasing the d/b on the lower end, the top either comes up to zero or positive. I aim for .5 °.  I start out to the low end and bring the d/b to zero. Then installing upwards, the low end comes up to .5 or might need a thicker aloquot.

    My dream tool for measuring the d/b would be a dial depth gage held in a stick gage similar to what John Hartman uses. The dial would be set to zero on the speaking length and the offset is read with the plunger situated over the backscale. Bass strings would have the initial tare set with the gage body on the wrap and the plunger zeroed out on the core.

    ------------------------------
    Regards,

    Jon Page
    mailto:jonpage@pianocapecod.com
    http://www.pianocapecod.com
    ------------------------------



  • 14.  RE: Advice needed

    Posted 02-18-2020 15:33
    Unfortunately I cannot provide any photos.  The grand is a Gors and Kallmann and is 1.63m. I also do not think this piano originally had duplex bars. 

    Thanks very much Jon! What is the tool you're using in the second photo and how does it work?

    ------------------------------
    Mark Davis
    Piano Tuner/Technician
    ------------------------------



  • 15.  RE: Advice needed

    Registered Piano Technician
    Posted 02-18-2020 21:48
    Some of us maintain that the only way to ACCURATELY figure out the DB is to eliminate tension and therefore remove any "wild cards". 

    Pwg

    ------------------------------
    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
    ------------------------------



  • 16.  RE: Advice needed

    Posted 02-18-2020 21:56
    The wooden tool is John Hartman's gage for measuring the string's declination.  If it were to be configured with a dial gage/plunger, one could know exactly what the angle is; very quickly.

    ------------------------------
    Regards,

    Jon Page
    mailto:jonpage@pianocapecod.com
    http://www.pianocapecod.com
    ------------------------------



  • 17.  RE: Advice needed

    Posted 02-19-2020 00:32
    Thanks Jon. 
    So, the brass halfrounds are what you installed? If the brass halfrounds were not installed, there would be quite a slope/angle down from the speaking length side of the bridge to the hitch pin. Using the John Hartman tool, what would the angle be without the halfrounds installed and would that angle be an indication of DB and the amount of DB?

    ------------------------------
    Mark Davis
    Piano Tuner/Technician
    ------------------------------



  • 18.  RE: Advice needed

    Posted 02-19-2020 07:52
    The wooden tool is a measuring gage. One would use Feeler Gages to ascertain the gap between the wire and the tool in the backscale. Notice in the photo that there is a space between the tool and the wire at the duplex. The amount of this gap is dependent on the distance it is from the front hitch pin. There is a formula to determine the offset for a given distance and desired angle. A Lowell D/B Bubble Gage measures the offset. There's lots of info in the archives.

    ------------------------------
    Regards,

    Jon Page
    mailto:jonpage@pianocapecod.com
    http://www.pianocapecod.com
    ------------------------------



  • 19.  RE: Advice needed

    Posted 02-19-2020 08:01
    Peter,  DB is about the reaction of the board's structure to down force on the bridge, caused by string tension. DB without tension is a guess and/or wishful thinking. Please explain how you think tension is a "wildcard" in measuring DB...makes no sense to me at all.

    ------------------------------
    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 20.  RE: Advice needed

    Posted 02-19-2020 09:16
    Jim I. wrote:  "Peter,  DB is about the reaction of the board's structure to down force on the bridge, caused by string tension. DB without tension is a guess and/or wishful thinking. Please explain how you think tension is a "wildcard" in measuring DB...makes no sense to me at all."

    Exactly. Ditto to what Jim wrote....


    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 21.  RE: Advice needed

    Posted 02-19-2020 09:11
    Thanks for explaining Jon. I see the gap now that you mention it. I get what you're saying and I will look into understanding the formula. Thanks once again!​

    ------------------------------
    Mark Davis
    Piano Tuner/Technician
    ------------------------------



  • 22.  RE: Advice needed

    Posted 02-19-2020 09:20
    Mark D wrote:  "Using the John Hartman tool, what would the angle be without the halfrounds installed and would that angle be an indication of DB and the amount of DB?"

    Downbearing IS an angular measurement. Yes, one can measure the amount of downbearing (a linear measurement), but then for that linear measurement to have any practical meaning, one needs to measure the distance from the bridge pin to the point of downbearing measurement and calculate the angle of downbearing.


    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 23.  RE: Advice needed

    Posted 02-19-2020 09:33
    FWIW, as a general response to Mark's original question, I tell a short story about doing a first-for-me the other day. I went to tune a new customer's 100 (or so - who knows) year old brand X fetal-grand piano sometime last mid-December. She had told me that some keys were slow. I saw that the old dead beast had been restrung at some point in recent (?) decades. Everything in this action was slow - keys, action centers, etc. I checked the few WAY-out-of-tune strings and found the tuning pins were so loose, they likely would not hold a tuning. All the while inspecting the piano, I listened while she told me how many gazillion $$ she paid for the piano and how wonderful it was. I told her I needed to reschedule and bring my bushing iron with me. She said fine and was not in a hurry. I never called her back. She called me a couple days ago to schedule repairs. I told her I couldn't get to her piano for at least a month. She realized (I could tell in her voice) that I didn't want to work on her piano. We said goodbye on good (-ish) terms with her indicating that she will call someone else who could come sooner (geez, I hope no local techs read this....).

    Now I know darn well that I should have told her exactly what I thought of her piano and that it wasn't worth putting any money into it. Since having heard her talk at length how wonderful it was, I just couldn't get up the courage to lay the facts out. I know I should have - I'm a wimp I guess. But this was the first time in over 20 years in this business that I've ever basically refused to work on a piano that an owner wanted fixed. I have recommended to many to take their pianos to the dump - but I've always been able to convince them of the wisdom of going that route. So this was a first for me!  :-(

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 24.  RE: Advice needed

    Posted 02-19-2020 09:48
    -----------------------------



  • 25.  RE: Advice needed

    Posted 02-19-2020 10:24
    Terry,  I feel your pain.  I have been becoming more and more disgusted by the sh..ty quality of "rebuilds" out there, such that I do not pull punches at all, and refuse to tune them as well. I have refused, on numerous occasions, to get involved, because the scope of neediness would leave me producing a horrible "rebuild" myself. I do try and council them to put their money to more effective use. Sometimes  I get somewhere with this line of reasoning, but more often than not, it goes nowhere. The worst case of this was....well if you must know...my own childhood piano which my mom was convinced was an antique of inestimable value. It was a beat department store stencil runt. But, it was, after all, rebuilt by "someone who worked at Steinway"!  Thing is, they never tell you about the said rebuilder, was that he was janitor, and at that, got fired for janitorial incompetence. 

    I mostly stick to my servicing my own work these days...at least this way, I know who the perpetrator was.

    ------------------------------
    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 26.  RE: Advice needed

    Registered Piano Technician
    Posted 02-19-2020 15:21
    Jim,

    I consider 20 tons if tension (with its unknown existing pressure on the SB) to be a huge wild card.  I also consider the fact that I cannot ascertain the fore/aft angle (if any deviation from dead flat) in a strung state also to be a wild card which can often give a totally erroneous reading. 

    If you or others have ways of dealing with these issues (beyond making assumptions) I'd be very interested. 

    Pwg

    ------------------------------
    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
    ------------------------------



  • 27.  RE: Advice needed

    Posted 02-19-2020 16:53
    Peter G. wrote: "I consider 20 tons if tension (with its unknown existing pressure on the SB) to be a huge wild card."

    Actually, the downward pressure the strings exert on the soundboard is fairly easy to calculate if you know the downbearing angle and the string tension....


    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 28.  RE: Advice needed

    Registered Piano Technician
    Posted 02-19-2020 17:12
    Terry,

    The very fact that you don't KNOW the precise angle because you don't KNOW how much pressure is actually being exerted on the board because you don't KNOW how much crown the board had when it was loaded not do you KNOW how much resistance the board is exerting...

    Like I said, if you DO KNOW how to calculate all these things in a loaded dynamic system like this, you're way ahead of me and I applaud you. 

    Pwg

    ------------------------------
    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
    ------------------------------



  • 29.  RE: Advice needed

    Posted 02-19-2020 20:20
    you do know the precise angle if you are measuring it with a digital machinists angle gauge, which has been posted numerous times over the years. 

    Given that reading, taken as a composite angle, the (sine of the composite angle x tension) = DB in lbs.   If you are anal enough measure each string, you can add up the whole strung board at tension.  

    However, precision is really not that necessary, in my opinion, as we are looking for a bandwidth of possible DB's. Personally, as my pianos get better and better, I am backing the DB off to only enough to insure adequate termination at that terrible bridge pin termination, plus a little extra to insure you always have decent termination. At 88, I'm only shooting for 1 deg (which is like only .032" off of a straight line, graduating to less than 0.5 low tenor and 0.5-.03 deg in the bass. In my experience DB is really not all that necessary or picky, as long as it is minimized,. not crushing the bejesus out of the board structure, and helping the system terminate as well as can be expected at the front bridge pin.

    Mark's 4deg would crush the life out of a board, but I'd have to see how he measured it to see whether I trust those numbers or not. 


    ------------------------------
    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 30.  RE: Advice needed

    Registered Piano Technician
    Posted 02-19-2020 22:02
    Jim,

    Your description sounds essentially identical to what I'vd basically been doing for over 20 years. So I think in the final analysis we are of the same mind. Just perhaps going about it slightly differently. 

    I don't do new boards though anyway...just OEM's.

    Pwg

    ------------------------------
    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
    ------------------------------



  • 31.  RE: Advice needed

    Posted 02-20-2020 00:10
    Thanks to all. Your comments and advice have been helpful.
    ------------------------------
    Mark Davis
    Piano Tuner/Technician
    ------------------------------



  • 32.  RE: Advice needed

    Posted 02-20-2020 05:11
    All smart phones have a digital gauge (bubble) on board. Or you can download an app.

    ------------------------------
    Michiel van Loon
    MEPPEL
    +31655150644
    mvanloon@xs4all.nl
    ------------------------------



  • 33.  RE: Advice needed

    Posted 02-20-2020 05:20
    Peter G. wrote:  "The very fact that you don't KNOW the precise angle because you don't KNOW how much pressure is actually being exerted on the board because you don't KNOW how much crown the board had when it was loaded not do you KNOW how much resistance the board is exerting...

    Like I said, if you DO KNOW how to calculate all these things in a loaded dynamic system like this, you're way ahead of me and I applaud you."

    Jim I. described the procedure to calculate the amount of downbearing correctly. That's all you need to know - the downbearing angle and the string tension. You do not need to know the original, or unloaded, amount of crown the soundboard might have had.

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 34.  RE: Advice needed

    Registered Piano Technician
    Posted 02-20-2020 10:50
    The subject of DB has been debated for as long as I've been in the business and longer. I have come to believe that there is a reasonable window within which things work pretty well. Extremes (e.g. more is better) tend to cause problems sooner or later. 

    I also have come to believe that there are more ways than one to figure this out. What I do not yet believe is that an accurate assessment can be made in a strung state, unless of course the person doing it has set the arrangement up, therefore knowing most of the parameters. But if there is empirical evidence that shows it can be done (i.e. several pianos measured and diagnosed with findings written down, then de-strung and analyzed, and concluded that the initial diagnosis was spot on), I'll take your word on it and seek to improve my diagnostic capabilities.  

    Personally, the only times I've actually been able to do this is when there is in fact WAY too much DB and I am seeing the symptoms as a cluster in other areas. In these cases I have in fact been correct several times (when I've had opportunity to prove it). I don't use angles or gauges. But I know some who do. 

    Pwg

    ------------------------------
    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
    ------------------------------



  • 35.  RE: Advice needed

    Posted 02-20-2020 10:55
    Peter, then I assume you disagree with Baldwin's method for setting d/b with vertical hitch pins. I've applied it on the few retro-fits I've done. It works.

    ------------------------------
    Regards,

    Jon Page
    mailto:jonpage@pianocapecod.com
    http://www.pianocapecod.com
    ------------------------------



  • 36.  RE: Advice needed

    Posted 02-20-2020 11:34
    Hey Jon - what is Baldwin's method for setting DB with their vertical pins?

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 37.  RE: Advice needed

    Posted 02-20-2020 11:52
    Terry, Here's what I have accumulated over the years from this list.

    ------------------------------
    Regards,

    Jon Page
    mailto:jonpage@pianocapecod.com
    http://www.pianocapecod.com
    ------------------------------

    Attachment(s)

    doc
    Baldwin accujust.doc   78 KB 1 version
    doc
    Baldwin_AccuJust.doc   47 KB 1 version


  • 38.  RE: Advice needed

    Posted 02-20-2020 11:28
    Peter G. wrote: "I have come to believe that there is a reasonable window within which things work pretty well."

    I presume by "things", you are speaking of downbearing. What you have said is largely true. Especially for new compression-crowned soundboards. Super-especially for older compression-crowned soundboards. Less so with rib crowned and supported soundboards.

    The range of acceptably performing downbearing angles depends much on the design of the soundboard.

    "I also have come to believe that there are more ways than one to figure this out. What I do not yet believe is that an accurate assessment can be made in a strung state, unless of course the person doing it has set the arrangement up, therefore knowing most of the parameters."

    I'm trying to follow what you are describing. "...figure this out..."  What is "this"? Downbearing? "...an accurate assessment can be made..." An accurate assessment of what? Downbearing?


    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 39.  RE: Advice needed

    Registered Piano Technician
    Posted 02-20-2020 22:08
    I think there may be a little confusion about what I am talking about. I'll try to clarify.

    I am NOT talking about setting up DB on a new or restrung piano. All (or most) of the needed parameters are in plain sight. (e.g. Baldwin accujust, etc)

    I AM talking about attempting to diagnose accurately the DB situation in a fully functioning piano where original available crown is unknown (because you weren't there to see it), how much DB was applied to it, what the stiffness factors are in the board, how the bridge top is angled (if any), etc, etc. 

    Now, I have been successful at identifying excessive DB in a strung piano, however this is largely due to a larger symptom set manifesting itself and I am making a diagnosis based on the full symptom picture, not any angle measurements or rocker gauge, or bubble gauge readings. I don't use any of those.

    I think the accujust system is great (but you must follow the directions ☺).

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 40.  RE: Advice needed

    Posted 02-21-2020 04:45
    Peter G. wrote: "Now, I have been successful at identifying excessive DB in a strung piano, however this is largely due to a larger symptom set manifesting itself and I am making a diagnosis based on the full symptom picture, not any angle measurements or rocker gauge, or bubble gauge readings. I don't use any of those."

    How can one identify excessive DB in a strung piano without knowing what the DB angles are?


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    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
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  • 41.  RE: Advice needed

    Registered Piano Technician
    Posted 02-21-2020 16:30
    Terry, 

    Well for one thing no, you can't measure how much excessive DB there is (accurately anyway, IMO), but you can identify the probability of its existence. I have identified a set of parameters that taken together as a set indicates a very high probability (I'll guess at 80%-90% chance) that the soundboard is overloaded with DB OR has specific areas of extreme overloading. 

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
    ------------------------------