<!doctype html public "-//w3c//dtd html 4.0 transitional//en"> <html> Hi Joe   As far as the reasoning for the ribs... take a gander at this picture with the shape of the bridge roughly drawn in. Seems to me they were maybe thinking that this ribbing pattern would support the bridge area against downbearing. One rib traces the bridge almost dead underneath for most of the bass lower treble. The two longest ribs run on either side, and along with the cross rib they perhaps were meant to hold the whole area up.     <img SRC="cid:part1.3FC7835A.DBFCDCD5@grieg.uib.no" height=480 width=640> Joseph Garrett wrote: <blockquote TYPE=CITE>RicB queried: "Ok... so ... would you hazard a suggestion at a crowning radius for the ribs, number of ribs to use, thickness,  and a basic pattern ? "</blockquote> <blockquote TYPE=CITE>Ric, I'll defer to Del on that one. My take would be about 1/3 to 1/2 of what is used on "modern" boards. However, the basic shape, etc. of Square boards, may dictate something else. Hmmmm? I'll ponder that for a bit. Best Regards, Joe Garrett, RPT, (Oregon)</blockquote> I'd sort of imagined perhaps something along these lines.... with a bit taller rib,( or at least less tapered heightwise) and perhaps a bit thinner.  I could just copy the old ribbing pattern with a bit stronger ribs, machine crowned I suppose, but I cant help feeling this is an oportunity to learn some new things, improve on the load bearing ability of the origional design, and hopefully keeping in the ball park relative to the origional sound picture this thing was meant to have.   <img SRC="cid:part2.3FC7835A.DBFCDCD5@grieg.uib.no" height=480 width=640>     -- Richard Brekne RPT, N.P.T.F. UiB, Bergen, Norway <A HREF="mailto:rbrekne@broadpark.no">mailto:rbrekne@broadpark.no</A> <A HREF="http://home.broadpark.no/~rbrekne/ricmain.html">http://home.broadpark.no/~rbrekne/ricmain.html</A> <A HREF="http://www.hf.uib.no/grieg/personer/cv_RB.html">http://www.hf.uib.no/grieg/personer/cv_RB.html</A>  </html>