Now that the ribs are in place, the next step is to install the linings. For those readers who are not violinmakers, the linings are thin strips of wood that are installed on the inside edge of the rib on both sides to provide strength for the ribs (once the mold is removed) and also provide a larger gluing surface to attach the plates to the ribs.
To prepare the linings, 8mm wide strips of spruce (or sometimes willow) are prepared. The strips are then reduced to a thickness of approximately 2mm:
Those who have been following this blog will recall that mortises were cut into the upper and lower blocks for the linings before the ribs were glued. In addition to those mortises, similar mortises are cut into the corner blocks using a small razor saw and chisel:
In this picture, you can see the mortises in the lower block and the lower corner blocks:
Before bending them to shape, the linings are cut into shorter strips and soaked in water:
They are then bent (roughly) into shape on the bending iron:
These pictures show the linings dry fit in place (i.e. not glued) – note that the small gaps between the linings and the rib will close when they are glued and clamped:
The linings are then glued into place and clamped with specially made clamps:
The bottom of each lining is waxed prior to gluing to avoid accidentally gluing it to the mold. Also, plastic protective strips are placed on the outside of the ribs to avoid damaging the ribs with the clamps.
Here is the rib structure with the linings glued and clamped into place:
Once the glue has dried and the clamps are removed, the blocks, ribs, and linings are trimmed to their final height (tapered from 32mm at the lower block to 30mm at the upper block):
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