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Titanium Bridge Pins

  • 1.  Titanium Bridge Pins

    Posted 11-06-2020 22:31
    Received my titanium wire yesterday. Thanks for the tip Jim. 

    So i tried two ways to cut it. First was using a cut off wheel on my grinder. It was kinda neat seeing the bright white sparks. Next i tried just using bolt cutters and that worked very well. Neat stuff, cant wait to try them out.

    -chris

    ------------------------------
    Chernobieff Piano Restorations
    "Where Tone is Key"
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Lenoir City, TN
    865-986-7720
    ------------------------------


  • 2.  RE: Titanium Bridge Pins

    Posted 11-06-2020 22:47
    Do experiment tonally, before jumping in whole hog. My experiments are promising, but incomplete as of this moment.

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



  • 3.  RE: Titanium Bridge Pins

    Posted 11-07-2020 01:16
    But of course.  I was limited to two sizes .078 and .125. Since there wasn't a middle size, I was leaning towards just applying it to my Cher-no-plex system in the high treble. I eliminate duplexes altogether now. Should be a fun experiment adding the titanium.
    -chris

    ------------------------------
    Chernobieff Piano Restorations
    "Where Tone is Key"
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Lenoir City, TN
    865-986-7720
    ------------------------------



  • 4.  RE: Titanium Bridge Pins

    Posted 11-07-2020 08:28
    Please report your results...

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



  • 5.  RE: Titanium Bridge Pins

    Registered Piano Technician
    Posted 11-07-2020 11:30
    Be careful if grinding.

    Titanium is classified as a combustible metal because it is easy to ignite. As with all metals, fine dust-like particles of titanium will ignite more readily than solid blocks. ... Titanium fires cannot be put out with water or carbon dioxide.

    John





  • 6.  RE: Titanium Bridge Pins

    Registered Piano Technician
    Posted 11-07-2020 15:53
    Perhaps you've already searched this out but there are makers of such pins.
    i.e. http://www.alliedtitanium.com/products/fasteners/springpins/vupdc_Results.php?Search.x=19&Search.y=6&Search=Search&S_UCatalogue=204&S_UMeasurementSystem=1&S_UGrade=5&S_UMaterial=1

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    Steven Rosenthal
    Honolulu HI
    808-521-7129
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  • 7.  RE: Titanium Bridge Pins

    Posted 11-07-2020 17:36
    Yes, there is a good shot some "dowel pins" are produced in all kinds of lengths and diameters.  In fact, if you look at Michael Spreeman's pics on his website, the pins he's using look very much like dowel pins. I chose to make my own for my first experiment. If I continue, and it pans out, I will talk to those titanium specialty suppliers about making a run. The other choice would be to hve a local screw machine shop make them out of wire for me. But personally I'm still in the R&D phase, so by hook or by crook works for now.

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



  • 8.  RE: Titanium Bridge Pins

    Posted 11-08-2020 08:45
    Jim-
    Vis a vis "experiment," perhaps you'd consider alternating steel and titanium unisons for part of the high treble to check for audible difference, assuming you could replace the lesser pins after the test tunings showed the difference.
    Incidentally, the clearest high treble I've heard was in a Sauter concert grand, which included lots of titanium parts and an ebony bridge cap in the treble.

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



  • 9.  RE: Titanium Bridge Pins

    Registered Piano Technician
    Posted 11-08-2020 09:00
    So my question is:

    WHY does titanium benefit the application here? (IOW what's actually going on?)

    Also (okay more than one question), what grade(s) of titanium alloy is being experimented with (as there are several)?

    Pwg


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



  • 10.  RE: Titanium Bridge Pins

    Posted 11-08-2020 10:24
    As to the why...please keep in mind this is all hypothetical. The reason I started messing with bridge pins, front back row spacing, and materials, is that the impedance model of soundboard disfunction, around notes 45-55 simply does not describe, to me, the totality of the system. All pianos, regardless of soundboard shape, grands and uprights, which have seriously different soundboard shapes, exhibit the same tendency to break up or have lousy sustain in this area. 

    I started to question whether the natural frequency of the pins themselves, were participating in the tonal breakup that happens in this frequency range, as the tonal challenge seems to be frequency thing. It is true, from the impedance model, that the density of soundboard modes in that frequency range, are extremely dense. This means it could be impossible to avoid an impedance match, regardless of the board design. (Impedance matches of driving frequency and board modes are to be avoided as they will be explosive sounding.) So I started to examine whether the mode densities were an unavoidable gottcha or whether some other vector might help mitigate the effect of mode density in this area.

    I started to question whether the frequency response of the pin's material could be involved, to some degree, in the tonal challenge in this area. Titanium  will have a different natural frequency in the pin material itself, because it has a different composition than steel, The thought was to offset the pin's frequency a bit. I don't know whether my hypothesis holds up, regarding the tonal breakup, and pin frequency. Tonally it appears to be different, but the area is still tonally challenged. 

    Stainless has been used, but the stainless is too hard, and the termination becomes quite noisy, as in M&H current iterations of stainless terminations, even after they started using a softer alloy of stainless. Titanium retains the stiffness of steel, but is quite soft...close to aluminum's hardness. So there will be a different filtering of partials because of the makeup of the termination material.

    As to why the hard pins are so noisy, we are flailing in the dark. It could be, as Ed Mcmorrow hypothesizes, that the hard pins do not let the string machine a groove to anchor them during vibration, whereas softer materials would allow that self machining. It could be the softer materials do not let longitudinal modes propagate past the pin. Explanations are pure guesses, at this point. But I do know, having experimented with Ed's FTDS of the last 5 or 6 years, there is something going on that is not completely explained by the impedance models. My trebles, and especially high trebles are really nice and getting better, the more I work various parts of the system other than the board. I'm getting outstanding high trebles and lower trebles with old boards that should not be perfoming this well according to the impedance model.  

    Also involved in experiments is front back spacing of the pins, 8mm at 13 degree offset in the high treble, 10mm at 13 degree offset  throughout the rest of the piano, including the bass​. This all by itself is, as far as how my tonal results are trending. I think is buying some very nice tonal improvements.

    As well, as Ed Sutton mentioned above, with Sauter's ebony caps, the choice of cap will filter partials differently. Will Truitt has been doing a raft of experimentation on this front, but I will let him discuss his work, if he chooses to. I will say, that Will's work turned me on to both the bridge pin/cap/pin orientation line of thought last year. I stopped by his shop to listen to some of the pin configurations he was experimenting with. I expected to hear no difference between configurations (he had laid out 4 or 5 different configurations right next t each other on a tenor section). I was floored by the fact that each iteration has its own signature...I didn't necessarily like them all, but, without a doubt each configuration had a signature. 

    So at this point, my thinking is that the termination on the bridge, which is an absolutely horrible termination  to begin with, has a lot more to do with piano tonal signatures and dysfunction, than the impedance model, which prioritizes soundboard ribbing and panel design, will have us believe.

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



  • 11.  RE: Titanium Bridge Pins

    Posted 11-08-2020 10:26
    On the grades of titanium...that's correct many grades of the material exist. I have only experimented with grade 5 because it was easiest to procure. Also because, not being a mettalurgist, I'd be shooting in the dark, choosing one grade over another, at least for now.

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



  • 12.  RE: Titanium Bridge Pins

    Registered Piano Technician
    Posted 11-08-2020 13:33
    Perhaps somewhat analogous to the difference between a vertically laminated bridge vs. a solid bridge and how each lends it's "signature" to the overall tonal envelope?

    Pwg

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



  • 13.  RE: Titanium Bridge Pins

    Posted 11-08-2020 13:39
    and cheap piano's plywood roots where tonally, the sound is absolutely inert

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



  • 14.  RE: Titanium Bridge Pins

    Registered Piano Technician
    Posted 11-08-2020 16:12
    The model I am finding most productive is to consider how the bridge/soundboard/string termination interacts with the Transverse and Longitudinal modes of the strings. My hypotheses is that mode mixing creates heterodynes between the two modes. Some false beats are a kind of heterodyne with this model.

    Experiments with "hard" string terminations sounding false support this hypotheses.

    Also, hard, "slippery" bridge pins seem to produce more falseness.

    Indications also seem to suggest that the degrees of freedom of the bridge soundboard in relation to the angular momentum of the string modes greatly affect heterodyning between modes.

    In essence it seems logical to conclude that longitudinal mode energy that is essentially inaudible can "distort" the precision of the string terminations as regards Transverse mode definition.

    ------------------------------
    Edward McMorrow
    Edmonds WA
    425-299-3431
    ------------------------------



  • 15.  RE: Titanium Bridge Pins

    Registered Piano Technician
    Posted 11-09-2020 02:39
    Here is another question to ask about this:
    Is the possible improvement in sound from a titanium pin (or any other type of pin) from a quality of the pin's conducting of sound or its lubricity?

    If a particular type of string has better lubricity, hence better rendering is that the cause of improvement (or deterioration) of the tone or is the conductance or other quality of the pin the cause?

    ------------------------------
    Blaine Hebert
    Duarte CA
    626-795-5170
    ------------------------------



  • 16.  RE: Titanium Bridge Pins

    Registered Piano Technician
    Posted 11-09-2020 06:37
    Ummm...Ed, is there any chance you could simplify your comment? I kinda get it but it's still bit over my head. Yes, I think you're on to something but if really like a "picture" I can relate to.


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



  • 17.  RE: Titanium Bridge Pins

    Posted 11-09-2020 08:06
    RE lubricity vs how the material conducts sound, I don't see how rendering would have a tonal effect, other than allowing easier tuning.

    Also just a caution, as you referred to the titanium as "improved sound"...I am still experimenting with the tonal results. So personally, I'm not yet stating that titanium improves the sound without qualification. It would be good to have others experiment. It may turn out that it improves one tonal aspect but degrades another...we need more data.

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



  • 18.  RE: Titanium Bridge Pins

    Registered Piano Technician
    Posted 11-09-2020 09:50
    Always keep in mind how stiffness of the wire affects behavior at the termination. An infinitely flexible string would reflect T-modes at the bridge without trying to slide up the stagger pin arrangement. That is why I place the back row of bridge pins 10 to 11mm behind the front row to use the string stiffness to reduce the ability of the string to climb the pin while the string is vibrating. (It still doesn't eliminate all false beats but seems to significantly reduce them.)

    I suspect that some false beats are caused by the L-modes "distorting" the T-mode. L-modes that are too high in frequency to directly hear.

    ------------------------------
    Edward McMorrow
    Edmonds WA
    425-299-3431
    ------------------------------



  • 19.  RE: Titanium Bridge Pins

    Registered Piano Technician
    Posted 11-12-2020 13:11
    I would like to try to experiment with titanium pins on a Steinway A that has very murky tone in the 5 or so notes leading to the tenor/treble break. Applying CA has had a very minimal effect on the false beating.

    Jim, have you experimented with changing out single unisons with titanium pins in an otherwise steel pinned bridge? Or maybe even half and half (front/back?)

    And do you make the spread 8-10 mm between front and back pins (I think I read that somewhere along this post) for the same reason as Ed, to stiffen the string?


    Joe Wiencek
    NYC




  • 20.  RE: Titanium Bridge Pins

    Posted 11-12-2020 15:00
    You will have to experiment...no data on this yet. If there are termination problems with the notch or pin holes, the titanium will not fix your problem. The termination must be in excellent condition, regardless of what other things you choose to do to the belly. Termination condition is maybe one of the biggest bangs for the buck in bellywork.

    I think just changing out the front pins would probably be as successful as changing both front and back, again assuming a good notch and tight pin holes.

    I use the 8-10mm front to back spacing to assist the termination, which is actually a pretty lousy termination. I think Ed's explanation makes sense.

    One caveat... if you move the back pins forward, you must do it with a jig or some other way to assure you do not wildly increase the termination angle.  I believe that the front back spacing traditionally used is more an artifact of laying out the bridge and merely putting front and back pins on opposite sides of a straight line drawn between agraffe and hitch. The length of front back spacing increases as wire diameter increases so they can still lay out the bridge using a straight line with pins on either side of the string. In my own work, I have a set of numerically laid out plexi 6 pin jigs which I ran on the bridgeport, designed to assure there is always a 13 deg string offset over the bridge, no matter the diameter of the wire.

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



  • 21.  RE: Titanium Bridge Pins

    Posted 11-12-2020 22:38
    Regarding the murky tone on the Steinway A.
    Assuming the soundboard has crown and that hammer voicing is not the issue, and recognizing that false beats are prevalent. 

    Several rebuilds back i was getting plagued with false beats on new bridge caps. I traced the problem to the wood itself. I switched to using Hickory and false beats are absolutely 100% gone. One thing that amazed me, was that i used the same drill bit for the appropriate bridge pin. In the hard rock maple i could pull the pin back out, in the hickory no way. I now have a simple rule of thumb, if you can leave a fingernail trail in the wood, its too soft. Hickory bends my fingernail nail. As Ed M has said many times and which is very important, the Capo must be shaped to a v-shape.

    Check the downbearing angles.
    Steinway's, and most other pianos, simply have way too much downbearing. I once had a Steinway S that had a 2 degree angle in the treble. This is not very good for a compression board IMO.  I have witnessed a board that when the downbearing was corrected the sustain time more than doubled.
     
    My perspective on the titanium pins was expressing interest to reduce weight. It will be interesting if there is a tonal change.

    Here's a recording of a piano with hickory caps, v-shaped capo,  that had a downbearing problem i corrected, and a removed duplex.. 
    https://www.youtube.com/watch?v=9byoWDaZHGc
    -chris




    ------------------------------
    Chernobieff Piano Restorations
    "Where Tone is Key"
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Lenoir City, TN
    865-986-7720
    ------------------------------



  • 22.  RE: Titanium Bridge Pins

    Posted 11-13-2020 10:08
    Sounds nice. I'd like to hear it after the dampers are in, as the treble borrows fundamental from the bass strings, but sounds like there is some nice life up there. I would like to see a pic of the whole treble areas including backscale, if you could do that. I have been extending backscale with vertical hitches and eliminating the aliquots, which really shorten backscale up there as well.

    Quartered hickory?

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



  • 23.  RE: Titanium Bridge Pins

    Posted 11-13-2020 10:34
    Also, with the long duplexes, one of the parameters of  Ed's FTDS is to ensure the long duplex avoids ratios that will create noise. How do you avoid potential noisy front duplex strings, which is the bane of the duplex idea?

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



  • 24.  RE: Titanium Bridge Pins

    Posted 11-13-2020 11:06
    Yes, It's quartered Hickory. I buy it plainsawn (all thats available in my neck of the woods) and cut it into half inch strips. Then glue the strips together alternating the angle of the grain to create a stable quartered cut. 

    I am very fond of the accu-adjust pins and would like to convert to those at every available opportunity, but that is up to the client. Extending the backscale can't hurt.

    I avoid front duplex "noise" by not having metal to metal contact with short segments. So I use the Hickory as a string rest and lengthen the segments. I learned about using wood as a "filter" from Darrell Fandrich when we were discussing piano design over an A.B.Chase Upright. The AB Chase termination had used a phospher bronze wire on a wood base. 

    -chris

    ------------------------------
    Chernobieff Piano Restorations
    "Where Tone is Key"
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Lenoir City, TN
    865-986-7720
    ------------------------------