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Newbie again! When I recently received my first US made tuning lever I was pleased that it appeared to fit very well on my Knight K10 28 year old pins. As I progressed through this early learning tuning stage I have raised the whole piano 20 cents to reach 440 (not that it is in tune yet!).

Gradually I notice that the tip fit was slacker than before but I always took the time to ensure that the tip was fully pressed home. Although my pin tops are nickel plated there is evidence of a brown deposit on the star slots of the lever tip. However I see no such deposit on the edges of the pins. Perhaps the deposit came from the tip of my now retired tuner's tip as I did not see any deposit, e.g. rust inside my new tip on arrival.

Today as I again sit to practice tuning I noticed that the very tip of all pins have shiny marks indicating that the tip has been bottoming. However on looking inside my new tip I see no evidence of a pin mark on its base. I therefore assume that it was the tuner's tip that was bottoming.

I have a vernier depth gauge but I don't see how this can be used to check for a pin/tip gap?

Sorry for being ignorant, but I wondering if the pin top actually SHOULD bottom on the tip so as to avoid taper lock?

("Taper lock" is a standard method of locking twist drills into a holder on a dripping machine tool or lathe)

Ian

No, the tip fit on the sides of the pins, not bottoming.

It may be in the way of tight fit, as you say.

may be use some "red" (white typos corrector fluid, or lipstick, on the top of a pin to see if it transfers in the tip)

your tip must be too large if it bottoms, we do not have always the ideal fit, with some tips. I stopped using US tips because they where sometime less easy to use on a variety of tuning pins. I did not really understand the reasons, out of the ones that have only a strip of star shape in the tip, The angle of the inside of the tip may differ , the Yamaha tips seem to be the most versatile, with possibly a less strong angle inside.

Hi Ian. There is a taper to a tuning pin of about 3 1/2 degrees per side (or roughly 1/16" per 1"). Manufacturers make tips and pins to some kind of +/- tolerance of this nominal taper amount. As tools wear and are renewed, the actual parts will wander to the extreme limits of the size or angular tolerances.

My understanding of the tolerancing is that the pins are toleranced to the plus side of the angular tolerance and the tips are toleranced to the minus side. What that means is that if there is a discrepancy on the fit between the two, they will still make contact down lower on the pin and the top of the pin might wiggle a bit from being under sized. This is better for wear and tear than the top of the pin contacting and the bottom of the tip wiggling around with slop. The larger the diameter of whats being turned, the less force needed on it (in regards to torque).

Unfortunately, some cheaper tuning tips will wear out rather quickly and the poor fit will cause rocking and generally accelerate the problem even more if a tuner keeps on using it.

It is very rare for the tip to lock on to a pin. The parts need to be a near exact match for angular contact between them and they rarely are in this pristine condition. Sometimes we encounter a bit of snagging between the two and its a PITA to remove the hammer without effecting the fine tune setting. I usually see this happen with low quality soft pins or tuning tips where material deformity allows them to conform to each others shape a little more easy. To remedy this, I will reposition the tip on the pin with as little pressure forcing it on as possible, set it , and usually it just pops off fairly easy or you can rock it off at a 90 degree angle to the string pull to minimize it throwing out the tuning.

I've never seen it when watching my tuner, but is it possible that my tuner hit each pin with a hammer to increase the friction? Its a 2-3mm shiny spot on the top of each pin.

Maybe this was done by my piano shop or even the manufacturer now defunct, Knight Pianos of London?

Anyhow it leads me to the next question. I always finish with a clockwise press but I read somewhere that some tuners finish with a pull linear to the pin longitudinal direction. Is that a proper technique to "fix" the pin or is it an old wives tale?

Ian

Most all the tips I use are long enough that there is no way the very top of the pin will touch anything inside the tip.

There are different ways and approaches to render the string and set the pin on tuning and a good tuner who understands the mechanics and physics of whats going on can likely achieve the same results from differing methods. I like to drop pitch a touch on a new string (just to free it up,especially on older pianos) and then I swing sharp of target and pound the key fairly hard in order to get the back part of the string to decent tension. I then use a series of medium strength strikes and render the string back to pitch. I give the pin a final light wiggle in both rotational directions and in leaning direction and listen for any shifting of pitch, just to make sure it is in a very neutral/natural position with no torsional flex or lean. I then take a heavy test blow to make sure its secure and then move on.

Did you buy a NewOctave tuning lever? The tool is fine but their tips degrade quite fast. I still use a NewOctave lever but replaced the tip with a high quality one. The NewOctave #2 tips are also less tight and fit too low compared to other brands.

I bought it from a reputable London piano parts supply house. They said it was US made but there is no brand marking. It is a fixed head design but all metal appears to be Chrome Vanadium not plated steel. I have now removed the rust deposit inside the tip using PTFE spray.

From looking at the New Global catalog I see pin punches so I now guess that my tuner has used one of these and hammer tapped each pin maybe to even out the torques.

Ian