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I know that many use measurements of movement with a the bridge or mid point with a set weight, to get them close. Some use measurements with fft analysis.

I use low tech. With violins I use free plate tones and weight for getting somewhere close. Then I flex. Then I to area tuning that seems to even things up. Then I'll check movement of the back and belly where the bridge or soundest will be. When it is all glued up, I'll play with it some more; but by that time it will be close.

I did that with the arch top, but that is a similar animal. I'd make it thinner, and smaller bars today, but it plays good. It is pretty loud, and has read sustain.

I know nothing about these early ladder braced guitars. The tinier baroque (9.5 X 14.5) I made has NO braces on the back. Seems fine. This small (11.5 wide 17 long) Stauffer has 3. Seems like a lot to me. I cut them down from what the plan said, 15, 17.7, 16 from 18, 21, 22. I think that might be somewhat close to a regular guitar now, but it might have 4 braces? Seems like severe overkill to me. Am I wrong?

It has nice flex north/south, and diagonally. It doesn't flex sideways because of the bracing. That seems so weird.

The free plate rings at mid A There are a lot of notes but the open e is there, and a low C#. Hold it by the center brace and you can hear an A below the A on a guitar. Probably my ears making that one up?

The belly is glued on the ribs, but it still rings nicely at mid F#, a minor third below the back. Who knows where the back will be glued on. F# on the e rings, and the b between. Again it has tall bracing, (6 mm wide and tapered to 1 or 2mm ) Tapping the top gives a lot of notes too. The heights are 19, 22, above the hole and 18 below, and 14 between the bridge and the lower block. I put a maple bridge plate on that the original didn't have.

Do those braces sound about right, or are they "production" braces?

The back moves .230 or so with a 7 lb. weight. The belly moves .03 at the sound hole with 42 pounds (6 go bars with 1 inch spring.) at the bridge. With the indicator 1/2 inch above the bridge it moves .02 at 7 pounds and .10 with 42. The plan is for 81 pounds of string tension. The sides are braced underneath. I don't think the bridge will rise 5mm. I hope not.

Are those kind of movements in the ballpark?

The brace on the belly that seems huge is the top one. Is it for "popping" the high notes?

Thanks for anything. Watching Ken Parker bracing makes me wonder about everything.

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Why be normal?

Ken I can't comment on your methodology but I wanted to add that when I started as a hobbyist Luthier my goal was to be the sort of Luthier who did a lot of things by feel and intuition. I'm not poo pooing tap tuning, I did and do that too and I like my results.

I'm speaking of a more romantic notion that before anyone gags on their spoon to me is all about becoming more one with the materials that we are fortunate to have.

Mario once posted that he made a small block of wood and put it in his pocket and carried it around. So I did it too and I still have the small block of BRW that I carried in my pocket even at my day job where I wore suits. I carried that block of wood for nearly two years.

I also learned to tap tune but went my own direction and used StroboSoft and a spectrum analyzer to visualize what I believed that I heard.

High tech certainly has a place in Lutherie but so do 400 year old methods, romance and appreciation for the bounty of this planet that we are so fortunate to have to craft our wares from.

My hats off to you for getting personal with your voicing of your instruments. Good going.

I did CNC machining for 30 years, before that I was a Neanderthal with hand machines. I made replacement backshafts, crankshafts, and ball head adjusting screws for punch presses with no digital readout even.
So I'm going back to that. Sort of.
I like acoustics because they always work. No plug needed. But you have to make them like race cars, not something like a Camry.
I'll try to build up a feel, a few measurements, and some tones, before and after gluing, to get what I'm after. I've only used tap tones as a measure of stiffness combined with weight. I've done an archtop, a baroque in G, and this small Stauffer, so they don't have a lot in common! After watching Ken Parker, I might do another archtop next.
I might have built a nice Camry.

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Why be normal?