Antique Mechanical Restorations
Restorations Since 1973

Steinway Duo-Art




My inexpensive camera could not capture the tone and subtle nuances produced from this wonderful instrument. The music was truly beautiful.


    Damper lever flanges are cleaned and re-glued on damper assembly.

    Damper heads scraped of old felt. Heads cleaned before being sprayed with black lacquer.



    Old junction block for tracker bar tubing shown behind new. The blocks are upside down in this photo. These cut out sections will fit in between existing piano action frame. This is an early system that is not as stable as in later Duo-Arts.

    View from underneath of keybed - looking up. New junction block now an intricate part of the key frame. The new block has to be exactly the same level as the old key frame. Two new blocks will be made to mate with the underside of this key frame. These new blocks carry the signal from the underside of the key frame to the stack.
    The factory used round head wood screws to attach the blocks to the underside of the key frame. They had long since stripped the holes. Notice the newly installed brass seats to accommodate steel bolts as in later Duo-Arts.



    Close up of new junction block.


    Keyboard with brass nipples through keys.
                     
    New action, keys cleaned and re-bushed, new tops.
    

    

    This mechanism has neve been restored. Old style expression mechanism. There is no crash valve and there are no internal accenting pouches. The accenting pouches are outboarded in a separate unit.




    Notice the tag reading "NORMAL SOFT".  A lever may be moved by had to "Soft" to limit the throw of the accordion pneumatics. Of course, the owner has to know the lever exists.

    Unit containing theme and accompaniment pouches.

 
    Spoolbox before.


    Spoolbox after.
 
    Unrestored stack showing brittle grey tubing breaking off. This stack was very well preserved.
 
    Restored stack before adjusting new plastic nuts.
 
    I get a kick out of this. After the Aeolian Company spends unlimited money building this player mechanism like a battleship, they decide to save money by conserving on these insignificant leather ovals. Notice the ovals to the right were left over scraps from the holes punched in the main gasket.
 
    The old cross valve plates warp due to their design. This photo shows the old plates after they have been stripped of the old nickel plating. I am polishing each one before having them re-plated. They are setting on quarter inch thick glass with fine sandpaper attached. The cross section seats are re-surfaced on the paper to make them flat again.
 
    New pouches are installed using leather. They are sealed with rubber cement to make them all consistent.
 
    The cross valve seats are shown with new nickel plating. Burnt shellac is used to seal them in place. All the old ports in the stack have had shellac run through to seal the old wood.
 
    The old celluloid bleeds have been removed. Instead of a separate elbow and nipple for each note, a single unit is installed in their place. The extra long elbow has a bleed hole in the center. The system is updated to a late style Duo-Art to make sure no air bleeds cross grain through the wood structure. The new elbows are made by Mel Septon.  
 
    Complete, unrestored external Duo-Art pump. In early Steinway Duo-Arts the pianos were not altered to accommodate the player mechanisms. The structural beams found on the underside of the old Steinway Duo-Arts have the beams running on diagonals to the flat side of the piano. This leaves no room for an internal pump. These pianos are true Steinways. That is, they are the same instruments (apart from elongated keys) as non-player Steinways. The remote pumps were often located directly underneath the grand piano, therefore, he phrase "cow and calf" is used to describe this arrangement.
    Although it's hard to tell. The exterior of the cabinet is mahogany and will be refinished to match the piano cabinet.
 
    Collectors refer to this as the steamboat pump. You'll understand why when you watch the video. 
    This pump spent most of its life sitting on a cement or dirt floor. The bottom has rotted out and will be replaced. Notice broken casting on the lower right hand side of the pump. The large wheel pulled by the four leather belts has broken to pieces. Some of these pumps used pot metal wheels. I'll be replacing it with a steel wheel from my parts collection. The original motor also came with the pump but it is not shown in this photo.
 
    Two layers of veneer have long since fallen off the very bottom. The rectangular hole in the upper right side is supposed to be there. The other odd shaped hole is from rotten wood. The screws holding the bottom on the to sides were so rusted I had to use a hole saw to cut around them to remove the bottom.
 
    Here the pump cabinet frame is shown upside down with the bottom removed. The first repairs are taking place.
 
    The six pump feeder bellows are stripped and re-hinged. The front stiffeners have been fashioned and are sitting on top of the pile.
 
    The old leather covered rollers were made of maple. The center holes were worn large so new ones are being made from pinblock material. 
    This novel pump design has no direct linkage from the crankshaft to drive the feeder bellows. Instead, these leather covered rollers are spring loaded against the cams. There are two opposing rollers per cam, one for each feeder.
 
    The pump crankshaft showing three cams.


    Since the electric motor is suspended on conveyor belt material (originally leather) no vibrations are carried to the cabinet. Only a slight sound can be heard with the front of the pump removed. With the front on, the pump runs silently. 













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