easier journey than I thought

Turns out, I think the only frame member which was far enough off vertical to require the labourious trimming process, was the spine.  So after five days of slowly sawing that timber end-to-end through its wide axis, I think I am now done with that operation, I don't need to continue on and saw all the way around the other sides, a longer distance than I have covered so far.  Phew!  It's like finding out that you don't need to backpack that next 100 mile stretch, you're already in the right place.

Keeping the existing faces of the other 2x4s, it was thus only necessary to trim the top (soundboard) and bottom plywood sheets, which I had cut slightly oversize.  I did this also with my Buck Bros. PVC saw, but without the guide, just following drawn lines.  Progress was so zippy, going through 3/16" plywood instead of the wide face of a 2x4.

Next up, I can finally start to fit the outer side lumber, i.e., the "case".  I'll use my mitre guide to make mitre cuts: finally the purpose for which it was intended!  It has been invaluable in these other, 90-degree applications, too.

I have been planning to use "glue-n-screw" to hold the outer case lumber against the frame pieces.  A straight line of black drywall screws down the center of each side: I thought they'd possibly even look somewhat decorative, slightly evocative of the inset decorations on some fancy Italian harpsichords.  But, now I'm thinking, clamps may be better.  Problem is, I don't have clamps.  Well, I have two.  I think I will need at least four more, and probably ones which can go wider than my 3" metal C-clamps.  Those proper carpenter's clamps seem to be pricey for what they are, but that's exactly what I need.  So I think I will build my own, out of 2x2s and threaded rod.  They will be a little less convenient than the real ones, I'll have to use a crescent wrench to tighten them in a somewhat tedious fashion.  But they should apply the right kind of pressure.  The Titebond II glue that I'm using should allow ample time to fit the glued lumber together, and then slowly clamp it up.

I was also planning glue-n-screw for the soundboard, and I might still do that, since the "right" way requires a dedicated shop space ("go bar" table).  Ways to construct a more-portable go-table are in play in my thoughts.  But another option is edge-molding: either glue-n-screw with the screws hidden by the molding, or perhaps the molding itself can be used to clamp down the edges of the soundboard.  The cut edges of the plywood look better than I thought they might, but still I think the overall visual effect would be better if the edges were overlapped by molding, and also if there were no screws.  Of course, part of my reason to have screws was to overturn established assumptions and draw attention to the fact that the construction methodology was quite different.  But since even I can't seem to resist the desire to have no screws showing, I can assume that others wanting to copy this design will also feel that desire: so I might as well work out how to do it in a simple manner, even though it deviates from the "minimum effort and construction complexity" principle, slightly.

Here's my little saw-guide-and-2x4 rig, reaching the end of my five day journey through wood.  I'm glad I didn't have to do this to all the other sides!  I had developed a pretty good rhythm; about three "bouts" of 256 saw-strokes each, give or take, with a rest in between; and then it would be time to move the guide down.  I could have probably figured a pretty close estimate of the total saw strokes to make this 8-foot cut, but let's just say, must be tens of thousands.