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NO! Santa is definitely true person. He employs all that help
Nick

Well, that's not a very good guess.

I am constantly improving and refining my tuning technique. I suspect this process will continue until I can no longer lift a tuning hammer. The objective is fewer hammer movements, with less wasted energy in terms of body movement and excess tension. I am constantly getting rid of steps and motions that can be bypassed by using a slightly different approach. Yes, I can already get to where I need to be. But, that doesn't mean that I am getting there in the most effective means possible. Every time I am able to simplify my approach, I realize what was not important and what was.

It probably wouldn't change anything for my normal daily approach. That is right. But, for special situations like overly tight tuning pins or highly angled bridge pins, I'm sure that it would. I essentially never impact the tuning pin going sharp. However, I often impact the pin going flat. However, if confronted with overly tight tuning pins, and it can be shown that the pin does in fact twist, then I would be comfortable impacting the pin in the sharp direction...just an example.

I impact the hammer sharp regularly with tight pins.

Peter Grey Piano Doctor

I set up the tuning pin in a pinblock slice, drilled a hole in the bottom and CA'd (yikes!) A wire in it as in the original mentioned demo. I took a video from the top. If ever I can figure out how post it I will. I will predict that the results will be open to interpretation. One will doubtlessly see what one wants to see. Of course what is missing is the tension from the wire.

Peter Grey Piano Doctor

I find it is easier to upload to youtube and then just add the link here.

Good luck, I am curious to see your video.

All the best.

Thanks for the tip Jean. Here it is.

I used 5 ply quartersawn maple pinblock stock, drilled a .250" hole, drove a 2/0 x 2.5" blued pin into the hole stopping at a point that would reasonably simulate the pin height with plate thickness and coil, etc. I drilled a hole in the bottom and attached a length of copper wire so as to multiply the viewable movement. I aligned the tuning hammer with the wire as best I could for clarity. I held my cell phone in the left hand above (a little shaky) and worked the hammer with my right. The torque on this pin is in OUTER SPACE. If I had to tune a whole piano with pins this tight I would be totally exhausted. The tuning hammer is an older factory style gooseneck hammer (so yes there is some flex) however the tip is permanently welded on with the socket aligned correctly to the shaft.

So, you can decide for yourself as to whether you think there is twisting going on. My personal opinion is that there is significant twist of the pin above the block, however once the pin starts moving and then stops, I would surmise that there is no residual twist left in the pin, or If there is it is, from a practical standpoint, negligible.

What is missing of course is the 24/7 pull of 160 lbs of tension on a wire. It is quite possible/probable that a slight twist would be induced in the pin as a result of this. Additionally, this is a brand new pinblock, nicely gripping the pin all the way through. A worn pinblock which is larger at the top of the hole and more grippy at the bottom of the hole might act differently. As I said, judge for yourself.

https://youtu.be/oMvrtDPWfZQ

Peter Grey Piano Doctor

Looks like twist to me.
Try adding a copper wire to the becket hole.

160 lb. of string tension equates to 20 inch pounds of torque, maybe 1/3 degree twist on the pin or 1/8" swing on the end of the tuning lever. Might get a better idea when I make my video. Could happen tonight.

Sure looks like twist to me.
This is all very interesting.

Nick

Very well done! Sur looks like twisting going on there.

Would be nice to see another video with a Fujan (or similar stiff lever) and the Gooseneck for comparison of the flex in levers. ( A totally different subject I know)

It does show that we naturally take twisting into account when we set the pin.

Thanks!

I am looking forward to seeing Jeff's video as well.

Good idea Gene! Why didn't I think of that? 😨

Jean,

I tried my Fujan hammer on it, but the pin was so tight that when I went in reverse it unscrewed my tip. Wire in the becket hole should fix any illusory dilemmas. My goal was to produce a worst case scenario. I believe that a reasonably fit pin would exhibit very little "twisting" action.

So essentially it appears (to me) that the majority of any twist is in the part of the pin outside of the block. POSSIBLY the type of block material could make a difference such as Falconwood, Delignit, Amberlite (or whatever Baldwin called their rock hard material), or even standard flatsawn multilam maple.

I'm sure others will improve on this.

Peter Grey Piano Doctor

If I remember Ron Nossman’s reasoning:
His custom pin blocks were designed to allow the bottom end of the pin to rotate much easier in the block and the top to have more grip on the pin where it’s needed.
The blocks were standard multilam with a 10mm diligent cap and the diligent material I believe was his design the company made for him.

Yes, I recall similarly. But I think he just band sawed it up and planed it. Rough on the blades though. He also had a "floating" (literally) drill press for boring in place. Mine is similar, but not floating.

Peter Grey Piano Doctor

Last night I took 3 tuning pins and drilled 1/8" holes, 1/2" deep, longitudinally in the foot and enlarged the becket holes to 1/8" I then epoxied slightly flattened 3/32" diameter aluminum rods in the holes. I will drill papa bear, mama bear, and baby bear holes in some pinblock material and hammer the pins in so the foot is flush with the bottom of the holes. The rods will be bent as to be very close to each other, perpendicular to the pin, and vertical to a point about halfway between the becket hole and the pinblock. This is to minimize both parallax error and flagpoling effects (think about it...). A card with printed graduations from left 10 degrees to right 10 degrees will be fastened to the rod attached to the foot of the pin. The radius of the graduations will be 11 inches, which is the length of a standard tuning lever. A notation will be made on the cards indicating the max torque of each pin. The pin will be turned back and forth a few times with the lever at the 3 o'clock position, to reduce any flagpole effect. The tuning lever will then be impacted with a wooden mallet to sorta, kinda, maybe, show how an impact technique might move the pin differently.

At least that's my plan. We'll see what happens. I promise every effort will be made to assure that no marine mammals are culturally exploited during the demo.

Trying to understand: by twist do you mean rotation within the pinblock, or a rotational distortion of the piin itself?

Here's torsion being tested, elastic and plastic:
https://www.youtube.com/watch?v=qPIug2sewFA

And here's a nice graphic of what happens to a shaft being twisted within the elastic range:
https://www.youtube.com/watch?v=1YTKedLQOa0

You can probably skip over the equations, which brought back memories of those statics and dynamics classes from the 80s.

Better specify who said what. A quote would be helpful. We are all on different pages of the music here.

All makes sense to me. Only the top of the pin seems to twist. Thanks. It is all very interesting.

"Here's torsion being tested, elastic and plastic:
https://www.youtube.com/watch?v=qPIug2sewFA"


That first video is useful. Seems to imply, to me, that a tuner can fairly easily put a tuning pin into elastic deformation.
So then the query arises, if the pin moves, does it "catch up" completely and so end up as it was before disturbence, or does it nearly catch up, but not quite, meaning the tuner has to release the top back to where the base is sitting.
Nick

Here is a cartoon depicting exactly what the urban legend is all about:
http://forum.pianoworld.com/ubbthreads.php/galleries/3070012/tuning-pin.html

Any rotation that may be happening above the pinblock is meaningless, because as soon as you remove the pressure on the hammer, it naturally goes away. There is nothing that we would need to do about it. The urban legend is that the twist of the pin happens below the surface and it gets temporarily trapped there. It later releases, and causes the string to go out of tune. So, the moral of that fairy tale is that we need to alter our tuning technique to compensate and release that terrible monster from bondage before we go to the next note. That is the entirety of what this discussion is all about. The reason the term "foot" of the tuning pin exists, is because techs have been saying for a long time that the head turns, and the foot doesn't, because of a twist in the tuning pin.

Any torsional or bending movement that takes place at the head of the pin naturally returns to its original state as soon as we let go of the hammer. Maybe the head bends, maybe the head twists, but either way, that doesn't really matter. It immediately pops right back into place when we let go of the hammer. So, this is not something that we need to compensate for by "setting the pin." Unfortunately, setting the pin means different thing to different people, but the point is, if a twist is happening only at the head, it couldn't stay in a twisted position when you remove the force. It naturally would have to go back to its original state. So, there is not change in tuning technique. The change in tuning technique only comes if the twist is trapped in the pinblock, and the foot has to catch up with the leg. That is what the urban legend is all about.