Steinway D #411101 Bridges glued to board

My sound board press is unique as it also doubles as a bridge press. After appling glue, I fasten the bridge to the board with temperary screws through the ribs where dowels will be installed later. The the board and bridges are placed in the press to add additional clamping pressure along the entire plane of the bridge.

After the glue has cured, the screws are removed from the holes in the ribs, and wooded dowels are installed through the ribs and into the bridge.

Steinway D #411101 Bridge notching

After the bridge cap is sanded, templates made from the original caps are located on the new cap and the information transfered to the new bridge. The bridge is then again dry fitted to the soundboard, and the soundboard is again dryfitted to the piano. The location of the marks for the pins are checked against the plate hitch pins and agraffes, and any necessary adjustments are made. On this piano one section was out od alignment by about 1/4". Yes, the factory does make errors, and ther rebuilder has the opportunity to correct them.

After the pin holes are frilled, each unison is carefully notched on both sides. This is one of th most tiring and demanding jobs in rebuilding. Finally the bridge pins are installed to complete the project.

Steinway D #411101 Setting the Bearing

Setting the bearing on a new sound board is one of the most demanding steps in the rebuilding process. An over simplified description of setting the bearing is this: adjusting the height of the bridge caps to a height that causes the strings on the strung piano to cause downbearing on the soundboard. It is important to have enough, but not too much. It is also determinded to some extent by the amount of crown in the board. So how do I accomplish this?

The bridge caps are intentionally made thicker than the originals so that there is extra material to remove to establish the correct bearing, which also establishes the thickness of the bridge. This varies from location to location on the bridge. A notch is cut in the cap to the desired height with the use of a string and a saw. This is done at about 10-12 spots on the bridge. The bridges are then removed and the tops planed to the height of the notches cut in the bridge cap.

Bridge cap planed and sanded and ready for patterns to mark out bridge for notching and pinning.