Sunday, 24 July 2016

Grand Regulation – part XXVII



Step no41: Rebush / lube pedals and trapwork  

This step is divided into two parts. Part I deals with the lyre and pedals. Part II concerns the trapwork. So important is the pedal / trapwork system that it should not be left unattended, ever. Each time a piano is serviced, whether it be for regular tunings, or for minor or major repair and regulation, the pedals and accompanying systems should always be checked. As I sit down to a piano for regular tuning and maintenance, I always take a quick look inside to see how dirty the soundboard is, making note of how old the piano is and what model or size it happens to be. As I install the felt muting strips, I first depress the sustain pedal to raise the wedge dampers, to keep them from getting pinched while installing the muting strips. While depressing the pedal, I make note whether it squeaks, feels out of adjustment, or possibly if the entire lyre assembly is loose or needs repairing.

If anything seems to need attention, I correct it before I proceed any further. Only a minute is needed to wiggle the three pedals to see if they are loose. While down there, Iook over the lyre to check if any glue joints seem to be breaking loose, and also check the condition of the felt and leather of the trapwork. When the pedals are found to be loose, the lyre is usually in need of being removed. The exception is for Steinways, or any other make where the pedals can be removed independently of the lyre. One of my lesser desires in life is to have to reinstall a Steinway, so if I don’t have to remove it, I won’t! How one person can hold a lyre up off the ground, make sure that two lyre braces fit into their proper slots, and still have a free hand to join the lyre to the connecting plate under the keybed is a wonder to me. Anyway, proceeding with Steinways, remove the plate in front of the pedals, keeping the screws orderly so that they can be installed into the same holes. Disengage the pedal rods from the back of the pedals and pull the three pedals out. Each pedal can be worked on separately. Unscrew the plate on the bottom side of the pedal and check the condition of the felt bearing. New Steinways have a nylon sleeve instead of felt. The nylon seems to wear out quickly, so I only use good grade key bushing cloth when re-felting  these pedals. Cut a strip of bushing cloth, put some VJ lube on the area of wear, and tighten the plate back onto the pedal.

Of all the pianos I work on, the Steinways are my favourite for repairing the pedals. The above procedure can’t take much more than five minutes. I carry strips of bushing cloth precut to fit Steinway pedals in my tool case to speed this repair even more. However, if the pedals are accessible from the bottom of the lyre, the lyre must of course be removed. Before turning the lyre upside down, take the three pedal rods out and lay them somewhere in order. There is nothing like getting the pedal rods mixed up for wasting time and effort! Unscrew the lyre box bottom, marking it if needed to reinstall it properly. The most common type of system used in this kind of a lyre is where the pedal pin slides inside a wooden dowel. Again, before removing, number these dowels to insure that they don’t get mixed up. Also, check to see if the exposed ends of the dowels are level with the lyre box. If not, they may become noisy. Glue shims onto the dowel to bring it up level. Rebush the dowel if needed, and lube with VJ lube. After reinstalling the pedals, check to see whether they have proper clearance in the pedal slot. Cloth balance rail punchings can be used to adjust the pedal right or left as needed. Note that the felt trim in the pedal slot is not meant to guide the pedals.

I remember years ago working on my first lyre like this. I didn’t have the foresight to number the dowels before I removed them. Neither did I pay much attention to the fact that the holes in the dowels were not centred, but rather off-set along the length of the dowel. I reinstalled the pedals, put the lyre back on the piano, and ...


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