Stieff Rebuild - Soundboard Preliminaries

An update on the Rebuild of Stieff 28334 has been a long time in coming.   I've been disappointed with my inability to focus energy on the project!   But progress has been made.

Cauls for gluing ribs to soundboard.  Note the concave or convex shape for top and bottom cauls.  These are sixty foot radiuses.

Prior to working with the actual ($$) new sound board, a sound board mockup was prepared using inexpensive quarter-inch plywood.   This step was taken to work out the bugs in the system before working with the new spruce board.

For the mockup, I used some clear fir as ribs that was available at no cost.  The picture below shows a jig with a 60 foot radius for shaping the topside of the ribs.

Below, the mockup progressed with the ribs fitted to the frame.

The mockup continued by gluing "ribs" to "sound board".  A few issues were noticed, and I was glad that I did this mockup, so I could proceed with confidence.  The cauls use mill hose pressurized at 30 psi.   I'm doing four at a time, and progressively moving cauls to a new position as glue dries.

Below is the completed "trial soundboard" which fit well when placed back in the frame.