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A new simple Baldwin accu adjust procedure

  • 1.  A new simple Baldwin accu adjust procedure

    Posted 01-21-2021 23:48
    The original setting procedure was basically stringing all notes to zero bearing,  Then after stringing, and dividing the long bridge into 3 sections, then starting at note 88 the first section would set the downbearing angle at 1.5 degrees. The next section at 1 degree, and the last section at half a degree, then the bass bridge would also be set to half a degree.

    However, i believe this puts too much overall downbearing on the boards. I ended up using the following procedure, and noticed a big improvement in the resonance. It takes a little longer to do, but i think its worth it and it shows that the accu adjust system is the best.

    Setting Plate height:
    Yes, using adjustable perimeter bolts are useful, but not really necessary for the accu-adjust.
    I use string to set the height of 88 and 21. Then i check the bass bridge #20 and #1, I aim for half a degree being about an eighth of an inch above the plate,  at all 4 points.

    Procedure:
    Start at note #21( or whatever the first note is on the long bridge). String the first pair, bring up to tension. Then using a bubble gauge, zero it out on the speaking length, then transfer to the back length and set to half a degree. Go to next pair. The plan is to start at the bottom of the long bridge and go all the way to to note 88. Then go to bass bridge, everything at half a degree. That's it, its that simple. It loads itself to equilibrium by the time you get half way.  If you switch to a steeper downbearing angle one third the way up, like Baldwin did, you would have to go back and double check the first strings, and then it becomes an ever increasing downbearing sequence which equals too much load. With this system, you go through it once and call it good.

    Bubble Gauges:
    I use a homemade adjustable type gauge with pencil lines on the bubble that are at half a degree increments. To get the accurate increments, i used a wixie and a long stick with a pivot on the bench. But basically a half a degree is a small movement on any bubble.

    I lately started using non adjustable and small bubble gauges. I would add a magnet to them. This way i could adjust the rear string angle and watch the bubble move simultaneously. 

    All the best!!!
    -chris






     ​​​​

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


  • 2.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-22-2021 09:15
    I agree with your  DB thoughts.

    At this point, I look at many "accepted" procedures from the perspective, not of what tonal effect were the manufacturer's chasing, but rather, how the procedures, in a manufacturing setting, were required to accommodate realities imposed by the manufacturing process itself.  

    For instance, down bearing...I currently am of the opinion that boards do not need to be loaded that heavily, if at all, to function well. I think the bearing is mainly to insure decent termination at the bridge pins, which is a horrible termination. I think DB is more a termination safety thing, rather than a board loading impedance thing. For instance, the 1.5, in the top section...this comes from the fact that, in the top section, with such short SL and back lengths, 1.5 deg represents a bridge height that is a scant .032" above zero bearing. That is a pretty tight tolerance with a non adjustable hitch, given the fact that deflection of the board under load has to be estimated.  Without adjustable hitches, 0.5 deg, is almost impossible to hit, so the 1.5 is a safety value.

    Because accurate low DB values are difficult to achieve across the compass, I always install vertical hitches in the top section, and bass section, and adjustable plate bolts throughout. I want bearing minimized, similar to Chris, and just positive in the bass...0.3 is fine for me in the bass. 0.5-1 deg in the top, and between  0.5 and  1.0 progressing down the long bridge. The combination of adjustable plate bolts, and vertical hitches in the top section and bass, gets me pretty close to the values I shoot for, though DB setting is and remains one of the hardest things for me to target with the precision I would like.

    Chris, do you load the board before setting DB, or, how do you estimate deflection when setting bridge height?


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



  • 3.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-22-2021 12:19
    Hi Jim,
    I do not pre -load the board at all, but the loading happens organically as you add more strings and bring them up to tension.  For the problem you state, i think starting at the bottom of the bridge would make more sense then, because the board is fully loaded by the time i get to the top, and its a true .5 degree.  Maybe i have become sensitive to the bubble, but a .5 degree seem like its more than ample to do the job.  Starting the DB process at the top with a 1.5 degree as a way to anticipate deflection seems like a bad strategy.   After i'm done stringing and setting downbearing, i go back and check the starting point and its never been negative. If it was I would probably just zero it out knowing the board is pushing back.   

    -chris

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



  • 4.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-22-2021 13:19
    I understand your post stringing DB procedure, though I use a didgital angle gauge to measure the composite bearing.

    My question regarding setting DB was referring not to the stringing part you described, but to setting bridge height before laying out the bridge, drilling and notching. Just curious whether you preload when setting bridge height, or how you estimate expected deflection if you don't preload, when setting bridge height.

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



  • 5.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-22-2021 15:17
    My goal was to take full advantage of the accu-adjust , one of which is the benefit of  doing bridge work on the bench, minus a dry fit for layout.  The bridges are uniform in height.  The crown will cause the strings to ride a little higher on the vertical pins in the middle, but not by much.  That's why i use the 88-21-20-1 as plate height markers  to set those a low as possible.

    -chris

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



  • 6.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-22-2021 13:24
      |   view attached
    I have done the opposite on a few pianos. DB was 1+ on A0 and zero or negative at the top of the bass bridge. I add shims in front of the hitch pins. Starting at A0 to .5 degrees. I usually have to increase their height by the time I'm half way up. At the top barely any shim height or none and it's .5 or zero.

    I used to use brass bar stock but now use brass tubing which I can flatten with stock inside for desired thickness. This produces a rounded front and back and looks better but is more time consuming to make.

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

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



  • 7.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-22-2021 14:08
    good idea on the adjustable thickness tubing...

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



  • 8.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-23-2021 00:20
    A couple pics of the DIY Bubble (which sits on the pair of strings) and the video shows the tools i use. BTW, The Knot shown in the picture is a End Knot used in wire fencing to fasten wire to a post. A better knot for the vertical pins because no tail is needed.

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



  • 9.  RE: A new simple Baldwin accu adjust procedure

    Registered Piano Technician
    Posted 01-23-2021 08:57
    I have long surmised that the reason why manufacturers tend to overload the board is not because they think it's better, but rather to try to ensure that there WILL be measurable DB throughout the warranty period.  Self-insurance.

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 10.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-23-2021 11:30
    Thank you for this discussion it's so on point with my struggles to set light down bearing, especially in the treble where even with adjustable perimeter bolts very little plate adjustment is available.
    Oh how nice it would be to have vertical hitch pins in that area.
    that is the answer although I can't imagine stripping a STEINWAY of it's beautiful rear Alloquots.
    I do grind them to lower slightly,as needed. If only they were adjustable.


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    Fenton Murray, RPT

    Fenton
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  • 11.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-23-2021 11:43
    <that is the answer although I can't imagine stripping a STEINWAY of it's beautiful rear Alloquots.

    Imagine away. The aliquots seriously reduce valuable backscale length, and,  in addition end up, almost always, with unintentionally high bearing values. Focus on the positive instead...how would you like to hear shimmering high treble sustain, instead of pitch flavored knocks.

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



  • 12.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-24-2021 00:10
    JIM would you be so kind to supply a product and source,
    are they roll pins?
    also, diameter and drillbit diameter.
    Do you drill by hand just an approximate vertical pin or do you spend time looking for an exact perpendicular to string plane?
    did they come through bottom of the plate?

    ------------------------------
    Fenton Murray, RPT

    Fenton
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  • 13.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-24-2021 00:31
    Grainger 7/32" x 1" roll pin
    Buy a drill press at harbor freight. Modify post to about a foot long.
    6" 7'32 drill bit
    Put board across piano
    Place drill press on board.
    Drill away..........................

    -chris

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



  • 14.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-24-2021 10:39
    Mcmaster-carr   3/16 420 stainless roll pin.  The drill bit on a roll pin will always be the stated size of the pin. So, in this case 3/16. However, I prefer to undersize the drill by .010", and come back after spraying the plate, with a 3/16" chucking reamer. A 3/16 bit to ream would be fine. Touch the hole entry with a countersink lightly, to help the new roll pin into the hole, without dinging the new paint.

    I do all my vertical hitch drilling in the piano before I even take out the plate or have removed strings...Make that before I remove plate and strings in the treble, and after I have removed strings in the bass, as the bass new holes are very close to the old hitches. A drill press and board, as Chris says, works for the drilling. I use a pneumatically fed Ingersoll Rand machine with a precision E8 collet, which is my set up for block drilling in the piano, and plate drilling. But a drill press and board, the same as you would use for block drilling in the piano would work fine. I would not hand drill.  I do ream the machine drilled undersized hole by hand after the plate has been sprayed, with a reamer chucked in a hand drill.

    Regarding placement of the new hole, on a Steinway in the high treble, there is a nice flat section, often, behind the existing hitches. I mark out the location of the new holes before taking the old strings off, following their pathways to the new hitch. Try to locate the new holes in the thickened part of the casting near and behind the area where the original pins are. 

    If your new hole is not near an existing hitch, drilling is quite easy. On the bass shelf, it can be trickier. In the bass, move the hole back, in line with string travel, and start the new hole center just behind what would be a tangent point of the old hole. The old hitches have been sliced off with a multi tool and ground flat to the plate. The new hole, will be rear half new hole, and front half intersecting the old pin itself, like a Venn Diagram. This seems chancy, but it works in practice well. It took me a while to trust it, but it works well. Sometimes placing a new hole on a bass shelf can be problematic, as the pin layout, like on the L I'm working on now, is crammed tight originally.

    Regarding drilling vertically, one might ask "vertical in relation to what", as the plate is not a flat item ?...That's why I drill in the piano. Vertical in relation to the top of the case works well, and makes it easier to think about.

    I orient the slot of the pin facing away from the strings.

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



  • 15.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-24-2021 18:42
    Thank you , Jim.
    My first attempt will likely be the top couple sections.
    I had to run down and look at a piano to understand you’re drilling half of the old pin and half new material on the bass riser
    No other place to drill


    Sent from my iPhone, please excuse typos, etc.
    Fenton Murray, RPT
    Cell 831-320-7042




  • 16.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-24-2021 18:35
    Understood!

    Sent from my iPhone, please excuse typos, etc.
    Fenton Murray, RPT
    Cell 831-320-7042




  • 17.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-25-2021 07:36
    For the treble pins, why not turn the string frame upsidedown and punch the pins out?

    I have removed the bass pins and used those holes, it's often not easy.
    If a hole becomes enlarged (don't ask); drill out to 5/16" (I think) and install a 5/16" tension pin for the 3/16" to fit inside.

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

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



  • 18.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-25-2021 07:40
      |   view attached
    I found a photo of a verticle hitch pin "bushing".

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

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



  • 19.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-25-2021 07:46
      |   view attached
    Another photo of a retro-fit.

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

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



  • 20.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-25-2021 07:53
      |   view attached
    An interesting work-around.

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

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



  • 21.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-25-2021 08:42
    Here's what I mean about moving bass hitches. Top circle is the original hitch location, pin sheared off, left in the hole and ground flat to the bass shelf. Bottom circle is the new pin hole



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



  • 22.  RE: A new simple Baldwin accu adjust procedure

    Registered Piano Technician
    Posted 01-27-2021 03:45
    Hi Jon:

    While the picture shown what look like brass washers to set bearing at the hitch pin, it also has the added benefit of floating the backscale speaking length all the way to the hitch pin.  I have seen a 40 year old August Forster 190 that floats the back scale with a single thickness of a brass washer this way.  There is no string rest felt, it is not needed.  In fact, they floated the back scale all the way up to 88.  In their case, bearing was set at the bridge and not at the hitch pin.  The purpose served was to raise the string just high enough that it does not contact the plate ahead of the hitch pin, thereby increasing the open back scale length. 

    There is no room on the shelf for a hitch pin behind the old hole in your picture, and there are many pianos where this is the case, such as an already strung Steinway O in my shop.  There seems to be no reason not to do this, where appropriate.  

    Will Truitt

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    William Truitt
    Bridgewater NH
    603-744-2277
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  • 23.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-25-2021 08:46
    I don't punch out the old ones, because often the original holes, like the L I'm working on, are drilled at an angle. Same with Chickerings. I think Masons are straight and bent back to the angle. Also, at least in the high treble, I'm looking for more backscale length.

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



  • 24.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-25-2021 10:45
    What I've done in the event of an angled pin is to apply MarineTex Epoxy Paste from underneath to half-way fill the hole. Once cured, I drill down from the top. I've used it to restore the edge on a split treble bridge pin line, still holding after 30 years.

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

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



  • 25.  RE: A new simple Baldwin accu adjust procedure

    Posted 01-26-2021 18:31
    Hey Jon,
    Another work around (and it doesn't look bad either), if the plate has a shelf in front of the hitch area. I have put a piece of hickory (with some felt glued on top) and used that to adjust downbearing. And its kind of a 2 for 1 as well.

    -chris

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