Pianotech

Prepping a set of tuning pins for stringing today I almost convinced myself that I didn't need to measure all of the pins beforehand. I like to measure all the pins and separate the ones that are a little under spec (.281" for 2/0) for use in the treble and all those over spec for use in the bass.

Above is a pin slightly under by about.001"

And then I came to this one.

That's a 4/0 pin in my box of 2/0s. Since these are going into a new block I would probably not have been happy with how that one turned. Guess I'll keep on measuring all the pins in the box.

Yikes! Good catch there Karl. Any others like that, or just the one? 

Peter Grey Piano Doctor 

Prepping a set of tuning pins for stringing today I almost convinced myself that I didn't need to measure all of the pins beforehand. I like to measure all the pins and separate the ones that are a little under spec (.281" for 2/0) for use in the treble and all those over spec for use in the bass.

Above is a pin slightly under by about.001"

And then I came to this one.

That's a 4/0 pin in my box of 2/0s. Since these are going into a new block I would probably not have been happy with how that one turned. Guess I'll keep on measuring all the pins in the box.

Prepping a set of tuning pins for stringing today I almost convinced myself that I didn't need to measure all of the pins beforehand. I like to measure all the pins and separate the ones that are a little under spec (.281" for 2/0) for use in the treble and all those over spec for use in the bass.

Above is a pin slightly under by about.001"

And then I came to this one.

That's a 4/0 pin in my box of 2/0s. Since these are going into a new block I would probably not have been happy with how that one turned. Guess I'll keep on measuring all the pins in the box.

Decades ago (in the '80s), when talk of out-of-tolerance tuning pins first emerged, I made a plywood jig with an indicator on top and a piece of aluminum angle (to match the thickness of the plywood), centered in the middle. The tuning pin lay in the angle, with the indicator plunger contacting the top side (as yours does). I could then read the diameter along the length of the pin by pulling it through, or any out-of-roundness by rotating it.

I never found anything like a 4/0 in a brand new box of 2/0s. But I quickly decided that if I was going to sort for deviations of ~2 mils, because of inaccuracies in the manufacturer's drawing of the rod stock, I would have to check for out-of-tolerance in each pin, both along its length and, where a deviation occurred, out-of-roundness there. It became a matter too many angels dancing on the body of each of these pins.

I still have my home-made jig, and will post a picture of it.

Prepping a set of tuning pins for stringing today I almost convinced myself that I didn't need to measure all of the pins beforehand. I like to measure all the pins and separate the ones that are a little under spec (.281" for 2/0) for use in the treble and all those over spec for use in the bass.

Above is a pin slightly under by about.001"

And then I came to this one.

That's a 4/0 pin in my box of 2/0s. Since these are going into a new block I would probably not have been happy with how that one turned. Guess I'll keep on measuring all the pins in the box.

I think about the same thing for centerpins. It is so easy to get them mixed up. That's why it's always good to double check with a gauge. I'm always surprised at what a huge difference .001 makes in a centerpin. 

Decades ago (in the '80s), when talk of out-of-tolerance tuning pins first emerged, I made a plywood jig with an indicator on top and a piece of aluminum angle (to match the thickness of the plywood), centered in the middle. The tuning pin lay in the angle, with the indicator plunger contacting the top side (as yours does). I could then read the diameter along the length of the pin by pulling it through, or any out-of-roundness by rotating it.

I never found anything like a 4/0 in a brand new box of 2/0s. But I quickly decided that if I was going to sort for deviations of ~2 mils, because of inaccuracies in the manufacturer's drawing of the rod stock, I would have to check for out-of-tolerance in each pin, both along its length and, where a deviation occurred, out-of-roundness there. It became a matter too many angels dancing on the body of each of these pins.

I still have my home-made jig, and will post a picture of it.

Prepping a set of tuning pins for stringing today I almost convinced myself that I didn't need to measure all of the pins beforehand. I like to measure all the pins and separate the ones that are a little under spec (.281" for 2/0) for use in the treble and all those over spec for use in the bass.

Above is a pin slightly under by about.001"

And then I came to this one.

That's a 4/0 pin in my box of 2/0s. Since these are going into a new block I would probably not have been happy with how that one turned. Guess I'll keep on measuring all the pins in the box.

Prepping a set of tuning pins for stringing today I almost convinced myself that I didn't need to measure all of the pins beforehand. I like to measure all the pins and separate the ones that are a little under spec (.281" for 2/0) for use in the treble and all those over spec for use in the bass.

Above is a pin slightly under by about.001"

And then I came to this one.

That's a 4/0 pin in my box of 2/0s. Since these are going into a new block I would probably not have been happy with how that one turned. Guess I'll keep on measuring all the pins in the box.

Prepping a set of tuning pins for stringing today I almost convinced myself that I didn't need to measure all of the pins beforehand. I like to measure all the pins and separate the ones that are a little under spec (.281" for 2/0) for use in the treble and all those over spec for use in the bass.

Above is a pin slightly under by about.001"

And then I came to this one.

That's a 4/0 pin in my box of 2/0s. Since these are going into a new block I would probably not have been happy with how that one turned. Guess I'll keep on measuring all the pins in the box.

I check mine and generally find up to a 0.07mm variance. 

Prepping a set of tuning pins for stringing today I almost convinced myself that I didn't need to measure all of the pins beforehand. I like to measure all the pins and separate the ones that are a little under spec (.281" for 2/0) for use in the treble and all those over spec for use in the bass.

Above is a pin slightly under by about.001"

And then I came to this one.

That's a 4/0 pin in my box of 2/0s. Since these are going into a new block I would probably not have been happy with how that one turned. Guess I'll keep on measuring all the pins in the box.

Tim,

Roughly .002" - .0025" variance? If my conversion is accurate. 

Peter Grey Piano Doctor 

I check mine and generally find up to a 0.07mm variance. 

Prepping a set of tuning pins for stringing today I almost convinced myself that I didn't need to measure all of the pins beforehand. I like to measure all the pins and separate the ones that are a little under spec (.281" for 2/0) for use in the treble and all those over spec for use in the bass.

Above is a pin slightly under by about.001"

And then I came to this one.

That's a 4/0 pin in my box of 2/0s. Since these are going into a new block I would probably not have been happy with how that one turned. Guess I'll keep on measuring all the pins in the box.

Peter,

I mean the difference in size between the biggest and smallest pin is around 0.07mm (0.0028"). I've used Denro primarily. 

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Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 07-31-2024 07:38
From: Peter Grey
Subject: Tuning pin surprise

Tim,

Roughly .002" - .0025" variance? If my conversion is accurate. 

Peter Grey Piano Doctor 

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Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 07-30-2024 23:01
From: Tim Foster
Subject: Tuning pin surprise

I check mine and generally find up to a 0.07mm variance. 

------------------------------
Tim Foster RPT
New Oxford PA
(470) 231-6074

Original Message:
Sent: 07-29-2024 15:17
From: Paul Rice
Subject: Tuning pin surprise

I have found the cheapest pins to be the most consistent and the premium brands to be the least consistent.
Sent from my iPhone


Original Message:
Sent: 7/28/2024 10:27:00 PM
From: Karl Roeder
Subject: Tuning pin surprise

Prepping a set of tuning pins for stringing today I almost convinced myself that I didn't need to measure all of the pins beforehand. I like to measure all the pins and separate the ones that are a little under spec (.281" for 2/0) for use in the treble and all those over spec for use in the bass.

Above is a pin slightly under by about.001"

And then I came to this one.

That's a 4/0 pin in my box of 2/0s. Since these are going into a new block I would probably not have been happy with how that one turned. Guess I'll keep on measuring all the pins in the box.

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Karl Roeder
Pompano Beach FL
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