Pianotech

I have some questions for everybody about pinning problems in Korean pianos.

I remember hearing about action centers that seize up as they warm up. That is, at first the piano seems fine but the more the pins move in their bushings, the tighter they get. I remember pin plating being nammed as the culprit, the plating flaking off and causing friction.

Is this phenomenon the same as the "contamination" Wim is talking about?

 Is this particular problem curable by repinning or like verdegris does the problem still lurk in the cloth.

I have some questions for everybody about pinning problems in Korean pianos.

I remember hearing about action centers that seize up as they warm up. That is, at first the piano seems fine but the more the pins move in their bushings, the tighter they get. I remember pin plating being nammed as the culprit, the plating flaking off and causing friction.

Is this phenomenon the same as the "contamination" Wim is talking about?

 Is this particular problem curable by repinning or like verdegris does the problem still lurk in the cloth.

it is too bad that, after all these years of pinning issues with Korean pianos, we have not gotten to the bottom of this issue through scientific investigation.

It is a bit embarrassing as an industry that rather than knowing what is going on, we are relegated to what "The Dude" would respond to by saying, "Well, that's like your opinion, man."

Alan

I have some questions for everybody about pinning problems in Korean pianos.

I remember hearing about action centers that seize up as they warm up. That is, at first the piano seems fine but the more the pins move in their bushings, the tighter they get. I remember pin plating being nammed as the culprit, the plating flaking off and causing friction.

Is this phenomenon the same as the "contamination" Wim is talking about?

 Is this particular problem curable by repinning or like verdegris does the problem still lurk in the cloth.

it is too bad that, after all these years of pinning issues with Korean pianos, we have not gotten to the bottom of this issue through scientific investigation.

It is a bit embarrassing as an industry that rather than knowing what is going on, we are relegated to what "The Dude" would respond to by saying, "Well, that's like your opinion, man."

Alan

I have some questions for everybody about pinning problems in Korean pianos.

I remember hearing about action centers that seize up as they warm up. That is, at first the piano seems fine but the more the pins move in their bushings, the tighter they get. I remember pin plating being nammed as the culprit, the plating flaking off and causing friction.

Is this phenomenon the same as the "contamination" Wim is talking about?

 Is this particular problem curable by repinning or like verdegris does the problem still lurk in the cloth.

it is too bad that, after all these years of pinning issues with Korean pianos, we have not gotten to the bottom of this issue through scientific investigation.

It is a bit embarrassing as an industry that rather than knowing what is going on, we are relegated to what "The Dude" would respond to by saying, "Well, that's like your opinion, man."

Alan

I have some questions for everybody about pinning problems in Korean pianos.

I remember hearing about action centers that seize up as they warm up. That is, at first the piano seems fine but the more the pins move in their bushings, the tighter they get. I remember pin plating being nammed as the culprit, the plating flaking off and causing friction.

Is this phenomenon the same as the "contamination" Wim is talking about?

 Is this particular problem curable by repinning or like verdegris does the problem still lurk in the cloth.

it is too bad that, after all these years of pinning issues with Korean pianos, we have not gotten to the bottom of this issue through scientific investigation.

It is a bit embarrassing as an industry that rather than knowing what is going on, we are relegated to what "The Dude" would respond to by saying, "Well, that's like your opinion, man."

Alan

I have some questions for everybody about pinning problems in Korean pianos.

I remember hearing about action centers that seize up as they warm up. That is, at first the piano seems fine but the more the pins move in their bushings, the tighter they get. I remember pin plating being nammed as the culprit, the plating flaking off and causing friction.

Is this phenomenon the same as the "contamination" Wim is talking about?

 Is this particular problem curable by repinning or like verdegris does the problem still lurk in the cloth.

I have some questions for everybody about pinning problems in Korean pianos.

I remember hearing about action centers that seize up as they warm up. That is, at first the piano seems fine but the more the pins move in their bushings, the tighter they get. I remember pin plating being nammed as the culprit, the plating flaking off and causing friction.

Is this phenomenon the same as the "contamination" Wim is talking about?

 Is this particular problem curable by repinning or like verdegris does the problem still lurk in the cloth.

I have some questions for everybody about pinning problems in Korean pianos.

I remember hearing about action centers that seize up as they warm up. That is, at first the piano seems fine but the more the pins move in their bushings, the tighter they get. I remember pin plating being nammed as the culprit, the plating flaking off and causing friction.

Is this phenomenon the same as the "contamination" Wim is talking about?

 Is this particular problem curable by repinning or like verdegris does the problem still lurk in the cloth.

Don -

I'd have to pin the problem on you!  You seem to place responsibility for lost info on 'us', but let's be real:
- have you (recently) produced a catchy, entertaining video on the subject and then put it behind a pay wall, do generate elevated perception of value?
- have you attempted to capitalized on other obnoxious efforts in media such as those seeking to promote the health benefits of WD40 by engaging in heated vituperousity?  (according to a different Donald, All press is good.)

All of which is to say thanks for taking the time to remind me, yet again.
- did you even try to get a sub-plot introduced in "Tuner" that would have been subliminally edifying and, simultaneously, elevated the overall social value of the film?

I have some questions for everybody about pinning problems in Korean pianos.

I remember hearing about action centers that seize up as they warm up. That is, at first the piano seems fine but the more the pins move in their bushings, the tighter they get. I remember pin plating being nammed as the culprit, the plating flaking off and causing friction.

Is this phenomenon the same as the "contamination" Wim is talking about?

 Is this particular problem curable by repinning or like verdegris does the problem still lurk in the cloth.

Ok, so I'm hearing that pin lubriction has bad effects long term. What about sizing with alcohal and water or VS Profelt or even Dampchaser tank additive?

Don -

I'd have to pin the problem on you!  You seem to place responsibility for lost info on 'us', but let's be real:
- have you (recently) produced a catchy, entertaining video on the subject and then put it behind a pay wall, do generate elevated perception of value?
- have you attempted to capitalized on other obnoxious efforts in media such as those seeking to promote the health benefits of WD40 by engaging in heated vituperousity?  (according to a different Donald, All press is good.)

All of which is to say thanks for taking the time to remind me, yet again.
- did you even try to get a sub-plot introduced in "Tuner" that would have been subliminally edifying and, simultaneously, elevated the overall social value of the film?

I have some questions for everybody about pinning problems in Korean pianos.

I remember hearing about action centers that seize up as they warm up. That is, at first the piano seems fine but the more the pins move in their bushings, the tighter they get. I remember pin plating being nammed as the culprit, the plating flaking off and causing friction.

Is this phenomenon the same as the "contamination" Wim is talking about?

 Is this particular problem curable by repinning or like verdegris does the problem still lurk in the cloth.

John P.,

Because of the fact that the PROBLEM is that the cloth in the bushing is basically bunching up in there, and putting serious pressure unevenly on the pin, lubrication does not fix that.  Remember, we're not talking about "normal" sluggish action centers. We're talking about SEIZED parts in relatively recent parts. Why are they seized? Don has researched and answered that. Removing the pin, reaming with a straight reamer, burnishing and installing a new pin, solves the problem permanently (in most cases). 

I used to be apprehensive about globally repinning things until I was exposed to more efficient methods of doing it (not to mention better tools too!) If that option can be a truly permanent fix it sure beats parts replacement.  IMHO

Peter Grey Piano Doctor 

Ok, so I'm hearing that pin lubriction has bad effects long term. What about sizing with alcohal and water or VS Profelt or even Dampchaser tank additive?

Don -

I'd have to pin the problem on you!  You seem to place responsibility for lost info on 'us', but let's be real:
- have you (recently) produced a catchy, entertaining video on the subject and then put it behind a pay wall, do generate elevated perception of value?
- have you attempted to capitalized on other obnoxious efforts in media such as those seeking to promote the health benefits of WD40 by engaging in heated vituperousity?  (according to a different Donald, All press is good.)

All of which is to say thanks for taking the time to remind me, yet again.
- did you even try to get a sub-plot introduced in "Tuner" that would have been subliminally edifying and, simultaneously, elevated the overall social value of the film?

I have some questions for everybody about pinning problems in Korean pianos.

I remember hearing about action centers that seize up as they warm up. That is, at first the piano seems fine but the more the pins move in their bushings, the tighter they get. I remember pin plating being nammed as the culprit, the plating flaking off and causing friction.

Is this phenomenon the same as the "contamination" Wim is talking about?

 Is this particular problem curable by repinning or like verdegris does the problem still lurk in the cloth.

Dave,

Nonetheless, it would seem to me that the fix is still the same, unless of course the entire bushing itself was destroyed.  

I would still tend to argue that the actual CAUSE of the failure is still related to the process Don described vs the other way around (but I wasn't there).

Peter Grey Piano Doctor 

Very possible that the problem is the action center pins. Look for contamination but also look to see if the end of the flange is not cut smoothly. This can catch on the felt and seize. Humidity changes causing the wood to swell will cause seizing centers which can be on the jack, the hammer, the rep-levers, damper underlevers. Pull out several whippens, test the jack with a gram gauge without the spring. If it beyond 1 to 2 grams remove the pin, ream and burnish the felt install a new pin with a clean cut

Order action brackers from Supply 88

According to Don Mannino, in most cases the solution to these pinning problems is to re-pin them properly. Ideally using the tools and techniques he designed and has taught over the years. 

Peter Grey Piano Doctor 

Very possible that the problem is the action center pins. Look for contamination but also look to see if the end of the flange is not cut smoothly. This can catch on the felt and seize. Humidity changes causing the wood to swell will cause seizing centers which can be on the jack, the hammer, the rep-levers, damper underlevers. Pull out several whippens, test the jack with a gram gauge without the spring. If it beyond 1 to 2 grams remove the pin, ream and burnish the felt install a new pin with a clean cut

Order action brackers from Supply 88

I agree with Peter.  I once did an experiment with various methods of curing sluggish centers.  I tried the Zapper (remember those?), using water/alcohol, Protek, Silicone oil and naptha, heat, and finally reaming with the Mannino reamers.  The only lasting cure was to ream.  If the pins have gunk on them, which you can see if you remove them, all of the rest of the pins are suspect and should be replaced.  I don't recall having to revisit sluggish centers when I replaced the pins and reamed them to fit.

According to Don Mannino, in most cases the solution to these pinning problems is to re-pin them properly. Ideally using the tools and techniques he designed and has taught over the years. 

Peter Grey Piano Doctor 

Very possible that the problem is the action center pins. Look for contamination but also look to see if the end of the flange is not cut smoothly. This can catch on the felt and seize. Humidity changes causing the wood to swell will cause seizing centers which can be on the jack, the hammer, the rep-levers, damper underlevers. Pull out several whippens, test the jack with a gram gauge without the spring. If it beyond 1 to 2 grams remove the pin, ream and burnish the felt install a new pin with a clean cut

Order action brackers from Supply 88

Hi, Keith.

There are two common friction problems in these actions. You've gotten some wonderful advice on the action center issue which is a potential problem. Before going in to treat, check the action vs the keys for sluggishness. If it's in the action centers, go ahead with repinning. If the keys are binding, take another tactic. You may have to address both. 

On these actions, the thickness of the wood at the bottom of the mortise can be too thick. There is a useful tool for "thicknessing" this point. Schaff 3156 - referred to as a Balance Pin Hole Reamer but this is a misnomer.