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
------------------------------
Original Message:
Sent: 01-24-2021 00:31
From: Chris Chernobieff
Subject: A new simple Baldwin accu adjust procedure
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
Original Message:
Sent: 01-24-2021 00:09
From: S. Fenton Murray
Subject: A new simple Baldwin accu adjust procedure
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
Original Message:
Sent: 01-23-2021 11:43
From: Jim Ialeggio
Subject: A new simple Baldwin accu adjust procedure
<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
Original Message:
Sent: 01-23-2021 11:29
From: S. Fenton Murray
Subject: A new simple Baldwin accu adjust procedure
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.
------------------------------
Fenton Murray, RPT
Fenton
Original Message:
Sent: 01-23-2021 08:57
From: Peter Grey
Subject: A new simple Baldwin accu adjust procedure
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
------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com
Original Message:
Sent: 01-23-2021 00:20
From: Chris Chernobieff
Subject: A new simple Baldwin accu adjust procedure
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
Original Message:
Sent: 01-22-2021 14:07
From: Jim Ialeggio
Subject: A new simple Baldwin accu adjust procedure
good idea on the adjustable thickness tubing...
------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
Original Message:
Sent: 01-22-2021 13:23
From: Jon Page
Subject: A new simple Baldwin accu adjust procedure
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
Original Message:
Sent: 01-22-2021 12:19
From: Chris Chernobieff
Subject: A new simple Baldwin accu adjust procedure
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
Original Message:
Sent: 01-22-2021 09:15
From: Jim Ialeggio
Subject: A new simple Baldwin accu adjust procedure
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
Original Message:
Sent: 01-21-2021 23:48
From: Chris Chernobieff
Subject: A new simple Baldwin accu adjust procedure
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
------------------------------