The impetus for my universal head idea started with wanting the best fit tip for any given pin. I have a pretty good assortment of tips but find changing them out to be time consuming and detrimental to the threading. I like the tip to grip the pin close to the coils and not at the tip of the pin (induces more torsion). I also like the handle positioned as close to the top of the pin as possible.
Early on, as in years and years ago, instead of swapping tips, I had them mounted on the heads and selected the appropriate combo for fit and elevation, even as limited as it was with 3 or 4 combos.
Last year, I came up with the idea of more cost effective universal heads mounted to a variety of tips. The Faulk hex extension gave me a resource. Select the best fit tip and insert the combo into the fitting on the handle. There would be no need to adjust your technique other than to compensate for the elevation.
Initially I found the effort needed to turn the pin was reduced from a single point system because of the six-sided bearing force (I assume). Maybe it was because of the over-size of the hex shaft giving a mechanical advantage. Which is why i'm now thinking of pursuing a larger diameter hex shaft.
A benefit of the vertical hex shaft is that the handle could move as close to the tip of the pin as the piano structure allowed. Close, at the tip of the pin for spinets and consoles and further out for handle clearance of a grand strut or vertical lid overhang.
Rather than allowing the lever to freely flop up and down the hex shaft, I'm pondering various means of inducing a fixed, although still easily moveable, vertical position.
Today, I tuned a M&H CC and S&S C. I used the old Hale one-piece head but the fit was at the tip on the pin of 2/0 pins. Fortunately, the pins were not overly tight and there was not a torsion issue with turning the pins. After those, I tuned a M&H console with the Faulk and a BKB #3 tip. I have no problem switching levers, even halfway thru a tuning. Sometimes, because I have options, I'll switch back and forth to decide which lever gives the quicker response.
Now, if I had a pre-setup series of tips mounted on universal heads, I could select the tip that best fit the pin and easily insert that into the handle and secure for structural clearances, rather than having to deal with whatever I have at hand and making do. I can and have done that for 40 years but would like a choice for options. Choice is always better.
So, it's still in the woiks...
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Regards,
Jon Page
Original Message:
Sent: 05-06-2016 16:34
From: Jim Ialeggio
Subject: 5 deg head lever clearance
<I don't see how the question you asked will produce the answer
you want
This is interesting, as in many instances in this work, I find the experience does not jive completely with the theoretical explanations.
For instance, in this case:
This 5 deg, relatively high vertical offset, very long lever combination I'm playing with(not convinced yet, but carefully observing)...I built this lever using a golf club handle for stringing new blocks...quick and dirty. It performed beautifully in this specific stringing/new pin excising task. My low tone torso did not experience the trips to the chiropractor it normally required...I mean the work was actually quite easy for me to do.
Ok...my intention was to leave the project there, just for stringing/pin exercising. But as usual understanding the limits of things is fun for me, so, I started messing about just for the willies of it, trying to tune with this very flexible set up. With its supposedly very high bending forces, in various orientations to the string plane, ie 3 and 9 as well as 6 over the stretcher (never 12 o'clock...too hard on my bod') I find what appears to be less bending force than anticipated, and a control at the pin which though requiring attention, do-able unto, for me, physically easier and intuitive. I think the intuitive may have more to do with my musculature working at its physical comfort level rather beyond my physical abilities more than anything else, due to the leverage...but not sure, still observing.
Then I take out my trad lever which measures about 17.5 deg. It was sold as a 20 deg head. I absolutely hate this particular lever...the brand of which I will not publish. Though the vertical offset of my golf club ( i refer to this fine tool as my 4 Iron), is greater than the above mentioned trad lever, 6" vs 4-3/8", and the 4 Iron's lever length is 1.5 times the length of the trad lever, in looking at the flex angles a twist imposes on the system, visually, the trad lever is forcing a level of bending on the pin that the 4 Iron is not. As well, I had another tech play with this high angle trad lever, and he couldn't tune with it either. The two of us have very different musculatures, by the way. I mention this, because I attentive to the possibility that the 4 iron has the potential of working nicely, because, and soley because it suits the physical limitation my musculature can support...but not totally sure this it the complete reason why it works.
So, not that a trad lever has to be this ridiculously high an angle, but, looking at the problem from accentuated and therefore easier to observe extremes, the simple explanation that "vertical offset is what matters, and how the force gets to the pin does not matter" is not a compete description of the forces at play. It is therefore, not completely correct in its incompleteness...forces are missing, which mess with the results.
One possibility is that how the force gets to the pin does present at least a second set of torques, to be accounted for. This is perhaps ignored in the usual description of simple lever forces. It is complex and I don't understand it, but the forces acting on the pin in the above accentuated example do not fit the accepted physical description. Applying turning torque with the high angle trad lever, even without applying all the torque needed to turn the pin, to reduce the effect of my personal low tone musculature, creates a clear visual, and proprioceptive tendency to towards greater pin flex than the low angle, higher vertical offset 4 Iron.
Why, I ask myself? One reason i can see regards different vector angles the two levers require the human applying the force, to use in applying force to the lever. The high angle trad lever forces the operator to divide his/her available turning force between a vertical and horizontal vector as they pull into the turning motion. The low angle 4 Iron only requires a simpler, more-singular, horizontal vector applied to the lever handle.
Still observing...
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Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026