Pianotech

Hello all,

While perusing the various blog entries I thought that I might opine on this topic. I hope it is still timely and of some interest.  The original post referenced a Steinway piano, so all my remarks have to do with rebuilding Steinways. 

The process of fitting the top of the pinblock to the bottom of the plate is something that should be taken very seriously as there is much more involved than meets the eye.  This is one of those points that we as rebuilders tend to overlook, or minimize the importance of,  that has irritated Steinway to the point of influencing their recent remarks and actions concerning rebuilders. This blog is not the place for a "how-to" on the subject but there are several basic principles we need to be aware of since much of what will happen in the future is based on fitting the top of the block to the plate web. Very briefly, and with most details left out, here goes:  The plate is suspended above the rim at a predetermined height with small spacer blocks representing the soundboard thickness, plate thickness and guesstimated acoustic dowel height which are laid on the inner rim.  When the block is shaped it is the first step of setting bearing, though we never think of it as such.  I specifically asked about the acoustic dowel height and was told that the goal is to have a relatively even bridge cap thickness from end to end when the down bearing is ultimately set. 

Think of the position of the plate and compare it to an airplane that is about to land.  We set the pitch or string angle to rise 1-2 degrees as it moves toward the tail of the piano, like pulling the nose of the airplane upward.  The strings are intentionally not set parallel to the keybed.  At the same time the roll is set.  This is the bass to treble string height relative to each other. Yaw is the "crab angle" set into the wind which would be us trying to set the strike line parallel to the front of the piano by fitting the edge of the PB to the plate flange. This will be tweaked when the the stack is fit to the keyframe during fore finishing.  Also, the plate elevation (string height) is set. This is all achieved, less the flange fit, with  one cut on the top of the pinblock matching it to the plate.  I think this is an absolute genius way of building a piano - not that it is without its problems.  These "old timer" piano builders were not stupid. Having to shape the top of the block was not to cover up a mistake. Every plate is going to be warped a different amount and each block will be matched accordingly and not to a specific measurement.  This is the epitome of hand craftsmanship and the fact that the measurements vary is not evidence of laziness or inability.  One of the pics shows how much the PB was cut down in the factory to get all these parameters within tolerance. Also, bending the plate down to the acoustic dowels is intentionally done with the future bridge height/down bearing  in mind, just pay attention during tear down.  It is not the sign of a poorly designed piano. 

When we have regulation problems that seem to be unsolvable, such as the problems of the CBS era, they can usually be traced back to quality control  in the plate positioning parameters. Many times the action can be made playable by custom bored hammers but this doesn't really solve the problem. If you're not aware of these parameters you can create some real headaches for yourself down the road.  Keep in mind that when the PB is shaped in the factory, the soundboard and bridges are not yet installed, so if you're installing a new block but keeping the original board and bridge without recapping you have a whole different set of obstacles to overcome to achieve proper down bearing by working backwards. 

I have never seen a plate that didn't warp when it cooled.  I've heard that some other high end manufacturers will surface grind the plate web to be flat so it sits flat on the top of the block. I've heard that Steinway does this now but I don't know for sure. I think this is a great idea, never the less, that is not the world I live in.  I regularly find  0.150" of warp in the center of the web, measured bass to treble.  (see photo).  I don't see any way that grinding the plate will work in a rebuilding situation.  If not planned for in advance in the casting process the plate could be too thin and also there will be little control for final plate position (think of the orientation of the airplane). The pinblock will always be too thick when first glued to the rim and the cornice and it will be doweled in, right? Because you doweled it in, right? Of course you did.  So now, if you just lower the warped plate onto the flat top surface of the new block and tighten the screws you're going to be pulling the block up against the PB dowels. The PB laminations can be pulled apart by the screws.  So if you're going to pull the gap together with the screws then don't dowel the PB to the cornice. This is WRONG if you're rebuilding a Steinway.  On most other pianos it's probably won't matter.  FWIW- "Stretcher" is a furniture term such as a cross-brace  between chair/table etc., legs.  "Cornice" is an architectural term, e.g. capital, frieze, pediment, triglyph, etc.    BTW -  Steinway patented the "glass bedding" of the top of the block as well as the edge to the flange.

After shaping the PB to the plate, the ends of the PB will be thinner than the middle by the amount of the warp.  Be aware of this if you are just going to restring the piano.  You might think you can get away with a longer tuning pin and then find them sticking out of the bottom of the PB in the bass or treble.  This is one of the downloaded pics where the tech's solution to his newly created problem was to grind off the ends of the tuning pins.  

Included are some pics of the modified router I use to shape the block. I realize that they are of limited value as most techs will never build something like this but maybe some can glean a few ideas.  The frame is made from unistrut bought at Home Depot. The drop tube has a bearing in its end next to the chuck and is made from a worn out 30-06 rifle barrel.  This allows the cutter to be 8" below the surface of the router and not whip at high rpm.

Hello all,

While perusing the various blog entries I thought that I might opine on this topic. I hope it is still timely and of some interest.  The original post referenced a Steinway piano, so all my remarks have to do with rebuilding Steinways. 

The process of fitting the top of the pinblock to the bottom of the plate is something that should be taken very seriously as there is much more involved than meets the eye.  This is one of those points that we as rebuilders tend to overlook, or minimize the importance of,  that has irritated Steinway to the point of influencing their recent remarks and actions concerning rebuilders. This blog is not the place for a "how-to" on the subject but there are several basic principles we need to be aware of since much of what will happen in the future is based on fitting the top of the block to the plate web. Very briefly, and with most details left out, here goes:  The plate is suspended above the rim at a predetermined height with small spacer blocks representing the soundboard thickness, plate thickness and guesstimated acoustic dowel height which are laid on the inner rim.  When the block is shaped it is the first step of setting bearing, though we never think of it as such.  I specifically asked about the acoustic dowel height and was told that the goal is to have a relatively even bridge cap thickness from end to end when the down bearing is ultimately set. 

Think of the position of the plate and compare it to an airplane that is about to land.  We set the pitch or string angle to rise 1-2 degrees as it moves toward the tail of the piano, like pulling the nose of the airplane upward.  The strings are intentionally not set parallel to the keybed.  At the same time the roll is set.  This is the bass to treble string height relative to each other. Yaw is the "crab angle" set into the wind which would be us trying to set the strike line parallel to the front of the piano by fitting the edge of the PB to the plate flange. This will be tweaked when the the stack is fit to the keyframe during fore finishing.  Also, the plate elevation (string height) is set. This is all achieved, less the flange fit, with  one cut on the top of the pinblock matching it to the plate.  I think this is an absolute genius way of building a piano - not that it is without its problems.  These "old timer" piano builders were not stupid. Having to shape the top of the block was not to cover up a mistake. Every plate is going to be warped a different amount and each block will be matched accordingly and not to a specific measurement.  This is the epitome of hand craftsmanship and the fact that the measurements vary is not evidence of laziness or inability.  One of the pics shows how much the PB was cut down in the factory to get all these parameters within tolerance. Also, bending the plate down to the acoustic dowels is intentionally done with the future bridge height/down bearing  in mind, just pay attention during tear down.  It is not the sign of a poorly designed piano. 

When we have regulation problems that seem to be unsolvable, such as the problems of the CBS era, they can usually be traced back to quality control  in the plate positioning parameters. Many times the action can be made playable by custom bored hammers but this doesn't really solve the problem. If you're not aware of these parameters you can create some real headaches for yourself down the road.  Keep in mind that when the PB is shaped in the factory, the soundboard and bridges are not yet installed, so if you're installing a new block but keeping the original board and bridge without recapping you have a whole different set of obstacles to overcome to achieve proper down bearing by working backwards. 

I have never seen a plate that didn't warp when it cooled.  I've heard that some other high end manufacturers will surface grind the plate web to be flat so it sits flat on the top of the block. I've heard that Steinway does this now but I don't know for sure. I think this is a great idea, never the less, that is not the world I live in.  I regularly find  0.150" of warp in the center of the web, measured bass to treble.  (see photo).  I don't see any way that grinding the plate will work in a rebuilding situation.  If not planned for in advance in the casting process the plate could be too thin and also there will be little control for final plate position (think of the orientation of the airplane). The pinblock will always be too thick when first glued to the rim and the cornice and it will be doweled in, right? Because you doweled it in, right? Of course you did.  So now, if you just lower the warped plate onto the flat top surface of the new block and tighten the screws you're going to be pulling the block up against the PB dowels. The PB laminations can be pulled apart by the screws.  So if you're going to pull the gap together with the screws then don't dowel the PB to the cornice. This is WRONG if you're rebuilding a Steinway.  On most other pianos it's probably won't matter.  FWIW- "Stretcher" is a furniture term such as a cross-brace  between chair/table etc., legs.  "Cornice" is an architectural term, e.g. capital, frieze, pediment, triglyph, etc.    BTW -  Steinway patented the "glass bedding" of the top of the block as well as the edge to the flange.

After shaping the PB to the plate, the ends of the PB will be thinner than the middle by the amount of the warp.  Be aware of this if you are just going to restring the piano.  You might think you can get away with a longer tuning pin and then find them sticking out of the bottom of the PB in the bass or treble.  This is one of the downloaded pics where the tech's solution to his newly created problem was to grind off the ends of the tuning pins.  

Included are some pics of the modified router I use to shape the block. I realize that they are of limited value as most techs will never build something like this but maybe some can glean a few ideas.  The frame is made from unistrut bought at Home Depot. The drop tube has a bearing in its end next to the chuck and is made from a worn out 30-06 rifle barrel.  This allows the cutter to be 8" below the surface of the router and not whip at high rpm.

Hello all,

While perusing the various blog entries I thought that I might opine on this topic. I hope it is still timely and of some interest.  The original post referenced a Steinway piano, so all my remarks have to do with rebuilding Steinways. 

The process of fitting the top of the pinblock to the bottom of the plate is something that should be taken very seriously as there is much more involved than meets the eye.  This is one of those points that we as rebuilders tend to overlook, or minimize the importance of,  that has irritated Steinway to the point of influencing their recent remarks and actions concerning rebuilders. This blog is not the place for a "how-to" on the subject but there are several basic principles we need to be aware of since much of what will happen in the future is based on fitting the top of the block to the plate web. Very briefly, and with most details left out, here goes:  The plate is suspended above the rim at a predetermined height with small spacer blocks representing the soundboard thickness, plate thickness and guesstimated acoustic dowel height which are laid on the inner rim.  When the block is shaped it is the first step of setting bearing, though we never think of it as such.  I specifically asked about the acoustic dowel height and was told that the goal is to have a relatively even bridge cap thickness from end to end when the down bearing is ultimately set. 

Think of the position of the plate and compare it to an airplane that is about to land.  We set the pitch or string angle to rise 1-2 degrees as it moves toward the tail of the piano, like pulling the nose of the airplane upward.  The strings are intentionally not set parallel to the keybed.  At the same time the roll is set.  This is the bass to treble string height relative to each other. Yaw is the "crab angle" set into the wind which would be us trying to set the strike line parallel to the front of the piano by fitting the edge of the PB to the plate flange. This will be tweaked when the the stack is fit to the keyframe during fore finishing.  Also, the plate elevation (string height) is set. This is all achieved, less the flange fit, with  one cut on the top of the pinblock matching it to the plate.  I think this is an absolute genius way of building a piano - not that it is without its problems.  These "old timer" piano builders were not stupid. Having to shape the top of the block was not to cover up a mistake. Every plate is going to be warped a different amount and each block will be matched accordingly and not to a specific measurement.  This is the epitome of hand craftsmanship and the fact that the measurements vary is not evidence of laziness or inability.  One of the pics shows how much the PB was cut down in the factory to get all these parameters within tolerance. Also, bending the plate down to the acoustic dowels is intentionally done with the future bridge height/down bearing  in mind, just pay attention during tear down.  It is not the sign of a poorly designed piano. 

When we have regulation problems that seem to be unsolvable, such as the problems of the CBS era, they can usually be traced back to quality control  in the plate positioning parameters. Many times the action can be made playable by custom bored hammers but this doesn't really solve the problem. If you're not aware of these parameters you can create some real headaches for yourself down the road.  Keep in mind that when the PB is shaped in the factory, the soundboard and bridges are not yet installed, so if you're installing a new block but keeping the original board and bridge without recapping you have a whole different set of obstacles to overcome to achieve proper down bearing by working backwards. 

I have never seen a plate that didn't warp when it cooled.  I've heard that some other high end manufacturers will surface grind the plate web to be flat so it sits flat on the top of the block. I've heard that Steinway does this now but I don't know for sure. I think this is a great idea, never the less, that is not the world I live in.  I regularly find  0.150" of warp in the center of the web, measured bass to treble.  (see photo).  I don't see any way that grinding the plate will work in a rebuilding situation.  If not planned for in advance in the casting process the plate could be too thin and also there will be little control for final plate position (think of the orientation of the airplane). The pinblock will always be too thick when first glued to the rim and the cornice and it will be doweled in, right? Because you doweled it in, right? Of course you did.  So now, if you just lower the warped plate onto the flat top surface of the new block and tighten the screws you're going to be pulling the block up against the PB dowels. The PB laminations can be pulled apart by the screws.  So if you're going to pull the gap together with the screws then don't dowel the PB to the cornice. This is WRONG if you're rebuilding a Steinway.  On most other pianos it's probably won't matter.  FWIW- "Stretcher" is a furniture term such as a cross-brace  between chair/table etc., legs.  "Cornice" is an architectural term, e.g. capital, frieze, pediment, triglyph, etc.    BTW -  Steinway patented the "glass bedding" of the top of the block as well as the edge to the flange.

After shaping the PB to the plate, the ends of the PB will be thinner than the middle by the amount of the warp.  Be aware of this if you are just going to restring the piano.  You might think you can get away with a longer tuning pin and then find them sticking out of the bottom of the PB in the bass or treble.  This is one of the downloaded pics where the tech's solution to his newly created problem was to grind off the ends of the tuning pins.  

Included are some pics of the modified router I use to shape the block. I realize that they are of limited value as most techs will never build something like this but maybe some can glean a few ideas.  The frame is made from unistrut bought at Home Depot. The drop tube has a bearing in its end next to the chuck and is made from a worn out 30-06 rifle barrel.  This allows the cutter to be 8" below the surface of the router and not whip at high rpm.

Hello all,

While perusing the various blog entries I thought that I might opine on this topic. I hope it is still timely and of some interest.  The original post referenced a Steinway piano, so all my remarks have to do with rebuilding Steinways. 

The process of fitting the top of the pinblock to the bottom of the plate is something that should be taken very seriously as there is much more involved than meets the eye.  This is one of those points that we as rebuilders tend to overlook, or minimize the importance of,  that has irritated Steinway to the point of influencing their recent remarks and actions concerning rebuilders. This blog is not the place for a "how-to" on the subject but there are several basic principles we need to be aware of since much of what will happen in the future is based on fitting the top of the block to the plate web. Very briefly, and with most details left out, here goes:  The plate is suspended above the rim at a predetermined height with small spacer blocks representing the soundboard thickness, plate thickness and guesstimated acoustic dowel height which are laid on the inner rim.  When the block is shaped it is the first step of setting bearing, though we never think of it as such.  I specifically asked about the acoustic dowel height and was told that the goal is to have a relatively even bridge cap thickness from end to end when the down bearing is ultimately set. 

Think of the position of the plate and compare it to an airplane that is about to land.  We set the pitch or string angle to rise 1-2 degrees as it moves toward the tail of the piano, like pulling the nose of the airplane upward.  The strings are intentionally not set parallel to the keybed.  At the same time the roll is set.  This is the bass to treble string height relative to each other. Yaw is the "crab angle" set into the wind which would be us trying to set the strike line parallel to the front of the piano by fitting the edge of the PB to the plate flange. This will be tweaked when the the stack is fit to the keyframe during fore finishing.  Also, the plate elevation (string height) is set. This is all achieved, less the flange fit, with  one cut on the top of the pinblock matching it to the plate.  I think this is an absolute genius way of building a piano - not that it is without its problems.  These "old timer" piano builders were not stupid. Having to shape the top of the block was not to cover up a mistake. Every plate is going to be warped a different amount and each block will be matched accordingly and not to a specific measurement.  This is the epitome of hand craftsmanship and the fact that the measurements vary is not evidence of laziness or inability.  One of the pics shows how much the PB was cut down in the factory to get all these parameters within tolerance. Also, bending the plate down to the acoustic dowels is intentionally done with the future bridge height/down bearing  in mind, just pay attention during tear down.  It is not the sign of a poorly designed piano. 

When we have regulation problems that seem to be unsolvable, such as the problems of the CBS era, they can usually be traced back to quality control  in the plate positioning parameters. Many times the action can be made playable by custom bored hammers but this doesn't really solve the problem. If you're not aware of these parameters you can create some real headaches for yourself down the road.  Keep in mind that when the PB is shaped in the factory, the soundboard and bridges are not yet installed, so if you're installing a new block but keeping the original board and bridge without recapping you have a whole different set of obstacles to overcome to achieve proper down bearing by working backwards. 

I have never seen a plate that didn't warp when it cooled.  I've heard that some other high end manufacturers will surface grind the plate web to be flat so it sits flat on the top of the block. I've heard that Steinway does this now but I don't know for sure. I think this is a great idea, never the less, that is not the world I live in.  I regularly find  0.150" of warp in the center of the web, measured bass to treble.  (see photo).  I don't see any way that grinding the plate will work in a rebuilding situation.  If not planned for in advance in the casting process the plate could be too thin and also there will be little control for final plate position (think of the orientation of the airplane). The pinblock will always be too thick when first glued to the rim and the cornice and it will be doweled in, right? Because you doweled it in, right? Of course you did.  So now, if you just lower the warped plate onto the flat top surface of the new block and tighten the screws you're going to be pulling the block up against the PB dowels. The PB laminations can be pulled apart by the screws.  So if you're going to pull the gap together with the screws then don't dowel the PB to the cornice. This is WRONG if you're rebuilding a Steinway.  On most other pianos it's probably won't matter.  FWIW- "Stretcher" is a furniture term such as a cross-brace  between chair/table etc., legs.  "Cornice" is an architectural term, e.g. capital, frieze, pediment, triglyph, etc.    BTW -  Steinway patented the "glass bedding" of the top of the block as well as the edge to the flange.

After shaping the PB to the plate, the ends of the PB will be thinner than the middle by the amount of the warp.  Be aware of this if you are just going to restring the piano.  You might think you can get away with a longer tuning pin and then find them sticking out of the bottom of the PB in the bass or treble.  This is one of the downloaded pics where the tech's solution to his newly created problem was to grind off the ends of the tuning pins.  

Included are some pics of the modified router I use to shape the block. I realize that they are of limited value as most techs will never build something like this but maybe some can glean a few ideas.  The frame is made from unistrut bought at Home Depot. The drop tube has a bearing in its end next to the chuck and is made from a worn out 30-06 rifle barrel.  This allows the cutter to be 8" below the surface of the router and not whip at high rpm.