Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Regulating an upright

The first task is to get [the new felts in and] all of the dampers lifting with the pedal at precisely the same time. Then comes the spoon adjustment. If only a few need adjusting, that can be done by tilting the action back and attempting an adjustment, then tilting it back to see if the lift is right or not on each one.

If they all really need adjustment, I know of another technique that is sure fire but involves lifting the action out of the piano to do it. Years ago on Pianotech, I suggested this technique for a console piano with the spoons all hopelessly out of order. The technician reported back that in the end, this technique had worked when all others had failed.

It is a technique that I saw some 30 years ago on a film shown at a PTG Chapter technical. For this, you need a damper regulating tool, however. Long nose pliers will not do.

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30 years later, I would not remember the title of the film or the company that made it but it was about damper regulation and showed how to make compound bends, and regulate spoons.

The spoon regulation idea is simple. Find one key where the spoon is already properly adjusted or do whatever you have to to get perhaps an end key right, such as tilting the action back, using a damper wire bender to adjust the spoon or use any other technique you may know. Mark or take note of which wippen that is. Remove the action and place it in a cradle or set it on a table or bench. Find a wedge of wood about the same size as a mute. Lift the damper rod and place the wedge under it until the marked wippen moves both the hammer and damper at the same time. Now, you can adjust all the rest of the spoons easily by bending the spoons fore or aft with a damper wire bending tool in about 5 minutes. Simply adjust the spoons so that all of the wippens make the hammer and damper move simultaneously.

For me, this was the tip of the Century because I could never figure out how to make one of those cock-eyed spoon bender tools work, not even for a single spoon! My hats off to anyone who can!

Thanks!

what do you mean by motion?

As for your regulation, this is what happens when action ratio is not the same for every key:



Your regulation gives you even keydip and even aftertouch for the cost of uneven lost motion (maybe even zero like on second key here because you don't really controlling this aspect) and uneven letoff distance (looks even from the key perspective but from hammer perspective it isn't).

Normal regulation in this case of uneven action ratios, gives you even lost motion, even letoff distance (and in result even hammer travel distance from rest rail to letoff) and even aftertouch for a cost of uneven keydip.

There is also another possibility mostly used in grands of compensating uneven action ratios with different hammer blow distance for each hammer, then you can get everything like above plus even keydip for a cost of uneven hammer blow distance, to do this in upright you would need to shim hammer rest rail felt under each hammer or something like that.

Your regulation probably works ok because there is not much variability in action ratios in upright pianos, from my limited experience there is usually more variability in grands.

As for your regulation, this is what happens when action ratio is not the same for every key:



Your regulation gives you even keydip and even aftertouch for the cost of uneven lost motion (maybe even zero like on second key here because you don't really controlling this aspect) and uneven letoff distance (looks even from the key perspective but from hammer perspective it isn't).

Normal regulation in this case of uneven action ratios, gives you even lost motion, even letoff distance (and in result even hammer travel distance from rest rail to letoff) and even aftertouch for a cost of uneven keydip.

There is also another possibility mostly used in grands of compensating uneven action ratios with different hammer blow distance for each hammer, then you can get everything like above plus even keydip for a cost of uneven hammer blow distance, to do this in upright you would need to shim hammer rest rail felt under each hammer or something like that.

Your regulation probably works ok because there is not much variability in action ratios in upright pianos, from my limited experience there is usually more variability in grands.