Action Manufacturing & Alignment

[jolly roger]

Hi Terry,
              I could almost write a book to answer all your questions.
But start looking at the action possitioning block on the left hand side of
the action drawer. Shim it to move action to the right, plane it to move
the action to the left.  Small adjustment will be made with the rails.  But
the majority of alignment is done via the frame and the positioning of the
frame.
Roger 



At 12:45 PM 6/24/01 -0400, you wrote:
>I have a question (well, a bunch actually) about aligning action parts at
>the manufacturing stage. When a manufacturer builds a piano, how do they
>align the capstans/wippens/hammer flange-shank-hammer? The only way it would
>make any sense to me is to stick the plate in the belly, string it, and then
>take the keyframe, install the hammer & wippen rail (of course you have
>already designed the geometry of the action) and position hammers to be
>located under the string strike point (considering the arc they travel, of
>course) with shanks parallel to one another and perpendicular to the hammer
>rail. Then you would install the wippens in a vertical plane with the hammer
>shanks - and of course then they would be perpendicular to their rail. Then
>you would cut your keys so that you could locate the capstans in that same
>planes of the hammer shanks & wippens. What you end up with here is an
>action that has is parts aligned. Or at least one that can be aligned. I
>realize various manufacturers are going to vary, but - Is this how they make
>them? Is this how they should make them? How do they align all the parts? Do
>they align all the parts? Do they align some of the parts?
>
>So how is it that sooooooooooooo many many actions I see have hammer shanks
>way off the perpendicular to the rail and wippens in the same manner. Some
>will have wippens that are far offset from the capstans. Some have wippens
>that are angled off severely from the vertical plane. Put three or four of
>these bends together in the same action and you got "sumpin' skwooey in St.
>Looie". Why do I see this? Why do I see so much of this?
>
>I'm working on the action from the 1920s (guessing at age) Knabe that I put
>a keybed in. The wippens are aligned OK (normal twists and bends and warps
>for an 80 year old bunch of little sticks) and are located over the capstans
>(imagine that :-)). The hammer shanks however, are angled toward the bass.
>Every one of them. Much more so in the treble with the angle lessening as
>you go toward the bass. The bass note #1 shank is almost directly over its
>respective wippen.
>
>I am going to talk to the representative for the hospital that owns this
>piano tomorrow to ask if he wants to consider rebuilding the action. The
>thing is trashed. Could do a band-aid job by replacing hammers, shanks and
>flanges, but it really need everything new. Even the keytop job is garbage.
>(I leveled the keys real nicely - Thanks Carl! (check is in the mail!). But
>when I sighted down the front edge I would see a few keys up or down a
>little.  I though "what the &*%$ (heck)". Then looking more closely, I
>realized that the keytops are like the Florida landscape - pretty flat
>compared to Wyoming, but when you go riding a bicycle (or look closely at a
>keytop), you realize that there are actually quite a few significant hills
>in Florida. I guess the keytop installer did not plane the wooden key tops
>down properly.)
>
>Anyway, just so I know what my possibilities are, can I consider a simple
>relocation of the action frame (not, of course, that it would be simple to
>actually do)? It would seem advantageous to me to move the keyframe down
>toward the bass to the point where note 88 hammer hits the desired string
>strike point AND is aligned with its wippen (or nearly so) and basically
>just try to not make alignment any worse, but yet improving the worst ones,
>maybe even moving the bass end in or out just a tiny tad if it helps out. Is
>this a reasonable thing to even consider? Seems to me I have to. I think the
>only way to make it perfect (or nearly so) would be to have a new keyframe,
>keys and action rails made.
>