Normally when someone speaks about the three "R's", you would expect to hear about reading, and writing, and arithmetic. But I want to write about the six "R's" that have been the source of some misunderstanding. These six "R's" are Repairing, Reconditioning, Regulating, Rebuilding, Remanufacturing, and Restoring. My purpose here is to clearly define and describe these terms so that you will be able to cut through the confusion and avoid misrepresentation of work that has been, or will be done to your piano. In addition to this paper, I have written on the topics of Reconditioning and Regulation. I would also refer you to the PTG Technical Bulletins on Regulation and Rebuilding/Reconditioning.
Repairing
This is as straightforward as it sounds. If something on a piano does not work, then it is repaired so that it does work correctly. For example, if a string breaks, then a new string would be installed. If an action part breaks, then it would be repaired or replaced in order to get that part to work correctly again. If the piano is a current model, then I prefer to use factory replacement parts when possible. For older pianos, I choose the best quality parts available. I might choose to use the term repairing even if I replaced all of the strings and tuning pins in a piano, if I did not replace the pinblock and soundboard.
Reconditioning
Reconditioning a piano involves making any repairs necessary, doing a thorough cleaning of the action, polishing and cleaning the case, replacing worn or broken parts only as needed, and doing minor adjustments to get the piano to play better. The problem here is that a piano may be repaired, reconditioned or regulated by a piano technician so that it plays well again, but the piano owner receives the impression that the piano has been totally rebuilt. I am making this distinction to try to eliminate any confusion.
Regulating
Regulation is the process of adjusting a piano to enable the piano play evenly, to maximize power, and to increase the speed of repetition. Regulating a piano will compensate for changes in the dimension of the parts due to wear and humidity changes. There are over 25 places to adjust the action of a vertical piano, and over 35 places to adjust the action of a grand piano. A few of the many steps that go into a typical regulation would include leveling the keys, making sure that there is no "lost motion" in the action, adjusting the hammers for maximum power, and adjusting the dampers and pedals for correct function. For more information on this subject, I have written a more detailed paper on the topic of Regulation. The Piano Technicians Guild also has a very good description of what is entailed in regulating a piano in the Technical Bulletin #2 on Regulation.
Rebuilding
Rebuilding a piano consists of complete disassembly, inspection, and replacement of all worn or unsuitable parts. The piano is then reassembled, adjusted, and tested to tight tolerances, to ensure that the piano plays and performs as a new piano. A complete rebuilding of a piano would involve replacing the soundboard and bridges, pinblock, strings and tuning pins, replacing all of the action parts, repairing the keys or making a new keyboard, and refinishing the case. A rebuilding of the action of a piano might involve replacing the action with a complete set of new action parts including hammers, shanks and flanges, wippens, dampers, key tops and key bushings.
Keep in mind that rebuilding a piano involves complete replacement of anything that does not perform its function as good as it did when it was new. I want to make this distinction to prevent any misunderstandings and confusion. Sometimes a piano will be represented as being rebuilt, either by the piano technician, piano owner, or seller, when it is obvious that an incomplete job was done. I prefer truth in labeling, and work that is done on a piano should be plainly and honestly described.
If a piano is in current production, it is preferred to use factory replacement parts to keep the piano original. Use of other than factory replacement parts can compromise the value and authenticity of the piano. If the piano maker is no longer in production, my choice would be to use the best possible parts that would not significantly alter the original design of the piano. For example, if a Steinway or Baldwin grand were being rebuilt, it is possible to buy complete sets of parts from the factory. If other than factory original parts are used, the piano owner should be notified, and the piano should be labeled in a prominent place that the piano has been customized.
Remanufacturing
There are many valid reasons for customizing a piano. The design of the piano has evolved considerably over the past three hundred years. There have been many advances in technology in the last few decades, and it is possible to remanufacture or redesign a piano so that it will actually outperform a comparable new piano. These custom design changes could include a completely different soundboard and rib design, a new stringing scale, major modifications to the bridges, and even a new set of keys and action. If you are concerned about keeping your piano original, you will want to have your piano rebuilt or restored. But if performance takes priority over originality, you will want to consider having your piano remanufactured by a competent technician.
Restoring
For historic or antique pianos, Restoration is the way to go. Museum pieces, even performance pianos, should be restored to their original condition. If genuine factory parts are not available, the existing parts should be rebuilt (cloth, leather and felt pieces replaced and springs replaced) if possible. When an "antique" piano is restored for a museum or a collector, the technician should strive for originality rather than attempting to "improve" on the original design or customize it in any way.
All original parts that are replaced should be preserved with the instrument and not discarded. This is a matter of conservation and preservation of an historical artifact in original condition. Some restorers will even look for parts from a piano of a similar age that have been discarded by others in order to put some semblance of authenticity back into "rebuilt" pianos... right down to the strings in some cases. Authenticity is the key word when discussing restoration of a piano.
A non-authentic piano is just another piano to a museum or a collector, and these instruments are no longer authentic because they are no longer original. Museums are a place where the past is preserved, not "modernized", "updated" or "improved" in any manner. If an owner wants their piano "customized" that's a different story all together, but if the owner is a museum or a collector, authenticity can be worth a thousand times what the improved performance might be worth.
(Many thanks to my friend and colleague, John Musselwhite, RPT, from whom I borrowed many of the ideas, sentences and word choices in the sections on rebuilding and restoring.)