Monday, February 21, 2011

Gluing in the Ribs and Soundboard

The ribs are glued to the underside of the soundboard and positioned by using the blueprint and carbon paper in various ways to eventually end up with rib outlines drawn on the bottom of the soundboard.  At that point, it's a matter of gluing the ribs into position and placing some flat weight on top of them while the glue sets.  I elected to use a square box of stained glass sample pieces and scraps as well as a couple kiln shelves and two five-pound weights.  The box was almost the exact size of the soundboard, so this worked perfectly.  The next evening, I scooped out the ends of all the ribs so they were down to approximately 1/16 of an inch.  My trusty Dremel with a sanding barrel zipped through those ends and made beautiful chamfers - not that anyone is going to see them.  But here are a couple of nice pictures of them.




My husband and I signed the underside of the soundboard and proceeded to glue it in place.  There is a huge difference between gluing in a large harpsichord soundboard in hot and humid Chicago and a small clavichord soundboard in the dead of winter.  Glue sets up fast when the board and the air are dry, so we had to work fast!


To shield the soundboard from being marred by the clamps, I took a wooden paint stick, cut it into four pieces, and used them to pad the surface.  Glue was spread all over the wrestplank, around the liners, and across the bellyrail.  I used spring/pinch clamps (newly purchased just for this application) in the mouse hole, and I used my c-clamps on the wrestplank.  


Along the other edges, I used 1/2x20 nails every three inches or so to hold the soundboard down on the liners.  These were placed close to the edge of the soundboard so that the decorative molding to come would cover them.  I handled the pinch clamps, and my husband handled the c-clamps as well as the nails (I was just no good with them), using our handy-dandy nail set.


All is drying now, and I plan to give it a good 24 hours before attempting to drill the tuning pin holes.