<How does it get out of the production facility like this.
the frame is an insane piece of engineering...literally. Having rebuilt these frames for a while as a subspecialty, on precision, dedicated equipment, I have seen spreads all over the place as a normal condition, I can tell you how easy it is to solder the rail in the wrong angle or wrong xyz location. Plus, keep in mind, the extruded rails often have a twist end to end. If you use a rare straight tube, paired with a twisted tube, spread will wander wildly. In a production setting there is no way they would or could spend the time we spent setting these up to solder. In the factory, you've got some ridiculous about of time to position and solder, and then out it goes, accuracy be damned. The trick is to avoid QC'ing the finished frames.
They spent a fair amount of time setting up a CNC to tightly broach the tube holes in the brass frames, a couple of years ago. But twisted extrusions, and tubes that bow after drilling are the name of the game, even with the CNC broaching. This means the entire frame takes on a twist, or can take off sometime in the first year, making bedding impossible without cranking the thing down and upsetting bedding. Split rails is another thing they have not been able to get a handle on in 150 years. This, mainly, because the fit of the tube/dowel, given the inside of the rail is not reamed, is impossible to get right anywhere near 100% of the time...plus, dowels move after drilling often as well.
The whole thing, not even taking into consideration how the tube ears make alignment/travel imprecise by design, is absolutely insane.
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Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
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Original Message:
Sent: 10-05-2021 06:08
From: Jon Page
Subject: Today's Dilemma
During a rebuild, the keyboard was replaced but the original action frame (split rails) was retained. (?) But at least it was painted gold.
There is 1.5 mm difference in the action spread from bass to treble. I'll shim to correct.
The HCH is 1 mm difference b~t.
To get 45 mm Blow Distance, the shanks rest on the felts (except #1). Notice the L/O button height between #1~2.
The customer would rather I cut the felts than the wood. Constructing a jig, etc...
Capstans align towards the rear of the cushion in the bass, center/front in the treble.
After correcting the spread, I'll move the bass bracket back (maybe 1 mm) to position the capstans equally; this will also have the strike surface contact the bass strings better.
How does it get out of the production facility like this? Last year, I had another re-re-do. I am not impressed.
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Regards,
Jon Page
mailto:jonpage@comcast.net
http://www.pianocapecod.com
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