After the ribs are indexed. I prepare them for gluing onto the soundboard. The cut outs for the reliefs in the ribs were saved and used as cauls for pressing the ribs. They are taped to the rib from where they were removed, and a hole is drilled through the indexing hole into the caul. a #7 bridge pin is inserted into the caul through the indexing hole, being left to protrude about 1/8". The ribs can then be dry-fitted onto the new panel, inserting the pins in the hole that were indexed into the new panel. Line are drawn to mark the location of the ribs before they are removed. the panel is now sealed in shellac everywhere but where glue will be applied. The original soundboard is used to set up the press for pressing the new board. When the panel has been brought down to 5% EMC, it is ready to be pressed. The press uses 100 PSI air pressure to clamp the ribs to the spruce panel. They are glues one at a time. Great care is taken to be sure that the ribs are placed in their indexing hole before pressure is applied to the rib. The whole process takes about 5" per rib. The loaded press is exerting about 15 tons of pressure on the soundboard.
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