Lochmann Coin-Operated Disc Piano

Lochmann Original 200 disc operated piano, single play, produced sometime in the early 1900s. 


Lochmann, manufacturer of fine disc music boxes, also produced several varieties of disc operated pianos made for the European market. 

    

This photo shows the restored piano in the collector's home. The front of the base cabinet hinges forward for disc storage.

Unrestored top section removed from base. The top gallery was missing as well as the front glass. The original finish was saved.

Similar in design to a disc operated music box, the star wheels (unrestored) can be seen clearly. The pressure bar with rollers is lowered in place after a disc has been put in place. Projections from the metal discs turn the star wheels to lift the hammers away from the strings. Spring loaded hammers then strike the strings.

Tuning pins (unrestored) are driven into a single plank of beech in European pianos of this era. It is impossible to tune the piano, the plank, called a pin block, has split and must be replaced. A new pinblock will be made of the finest quality  material, consisting of approximately 50 laminations per inch of thickness.

The back has been removed from the cabinet, seen on floor to the left. The glue failed long ago, the cabinet, shown on its side, was held together by nails. Here, a rubber hammer is used to coax the shelf from the side.

The sounding-board, (attached to the side facing down), came unglued from this back structure. The structure is being repaired before the soundboard is reinstalled. The wood has shrunk due to its age, and a large split must be filled on right.

The sounding-board, after having been repaired and refinished using shellac, is being reglued to the back structure. The new pinblock has been made and installed on right.

The plate (harp) has been installed and the holes for the tuning pins have been drilled. Stamped numbers highlighted in gold have been marked for the scale as it was originally. An accurate template of the original hole spacing had to be made to relocate each tuning pin.


 The symmetrical stringing scale places less stress on the back structure than typical overstrung scales. This design keeps the strings in tune much longer. 



The completed back with new strings has been installed in the cabinet. The unusual cone shaped wood piece at top is used to support the top edge of the music disc. There is another roller of a different style just above the tag in the bottom of this photo. Together, these two rollers "cup" the disc to keep the projections forced against the star wheels.

    


 The back is designed with the tuning pins at the bottom and the strings above. It's the only way for a piano tuner to access the pins. 


 On either side of the tuning pins, ten brass wires with small beater heads, make up the strikers for the tubular bells. 



The wood rail just above the hammer heads is the damper rail. The damper rail is operated from the disc as well. 

    

Springs attached to each action part, just below the star wheels, determine the force at which the hammer strikes each string. The springs are attached to a common bar. Adjusting the bar changes the volume of the piano.


Hammer heads are half as wide in comparison to a hand-played piano.

A total of ten nickel plated brass tubes make up the tubular chimes. Each tube is suspended by string that is tensioned with a thumb screw. The bells ring clearly with a silver tone. 


Close inspection of the end of each striker will show a piece of fiber contacts the bells.

A crank on the right side of the cabinet is connected to this main shaft inside coin mechanism compartment, located just below the tuning pins. The heavy steel cable supports an iron weight of approximately 100 pounds up the back of the cabinet. The weight is raised from the floor to the very top of the cabinet. When the weight reaches the top, a lever is activated which rings a bell to let you know it is time to stop winding.

The large gear of the coin mechanism was too deep to fit inside the cabinet, so the factory took the easy way out and cut a slot in back panel.

     

The coin is held in the brass cup on the far right, until the music gets underway, then it is dropped into the cash drawer.