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Where to start....
The numbers you give imply a break angle at the bridge of about 15 degrees. You probably can get away with less, which would reduce the down bearing load. Benedetto shows about a five degree break angle on his plan, and something on that order seems to work well. The only reason to use more than that is to keep the strings from rolling or sliding sideways when you pluck them, and with notches on the saddle top that's not happening.
In my break angle experiment I used a 'low' angle of about 6 degrees on a classical guitar, and it was sufficient. The 'normal' angle of 25 degrees didn't work any better. So long as the string stays in contact with the saddle top all through it's vibration cycle it will transfer all of the sound to the bridge, so there's no benefit to going to any higher break angle than you need to keep things in contact.
I used to use a 'hook' type tailpiece on my arch tops. It was 'L' shaped, with the lower arm of the 'L' bearing down on the tail block, to provide a pivot point below the edge of the top. The line of the strings points from the top of the saddle to the pivot point, so with that low pivot they would virtually go through the top at some point above the lower edge. The idea, of course, was 'more down bearing = more sound'. I ran a few experiments on one of them, using shims to alter the pivot point and checking the effect on the sound. As I moved the pivot further down from the edge the sound suddenly died at one point.
I'm not sure why the effect was so pronounced and sudden. I was not actually measuring the output at that time, since I had no computer, so I can't say what changed exactly. It could have been linked to the top thickness and arch shape, or maybe there was some more esoteric geometry involved. The compression force of the strings against the tail block would cause the top to pop up, and it may be that there is some sort of balance involved there, for example. But there was no doubt about the effect. These days I go for a minimal break angle in the 5-6 degree range.
Archtops lack a sound post to help keep the top from collapsing, and I've seen too many with the bridges cranked all the way up to keep the action usable as the top sinks slowly into the box. There are ways to shape and graduate the arch that help with that, but an ounce of prevention is worth a pound of cure, and minimizing the force that has to be dealt with makes a lot of sense.
Mention of the sound post brings us to the function of the violin bridge. Bowing the string pushes it across the top, more or less parallel to the plane of the top of the rim, and the contact of the bow damps 'vertical' string motion strongly. The top only really moves air to make sound in a loudspeaker-like 'vertical' motion, which bowed strings don't provide. The sound post acts to provide a stationary pivot point on the top near the treble foot of the bridge. This converts the bridge into a bell crank, with horizontal motion at the top being converted to a vertical force on the bass foot of the bridge. That is, of course, directly above the bass bar, which carries that force out along the top to produce the vertical motion that makes sound.
The top of the violin bridge is thin and light, so that it presents a fairly low impedance which comes reasonably close to that of the strings. This promotes the transfer of energy from the strings into the bridge. The bridge becomes thicker as you go down, until the feet are closer in mass and stiffness to the top at that point, again, making for a decent impedance match and good sound transfer. It serves a similar function in this respect to the bell on a horn, matching the high amplitude low impedance string/bore signal to the higher impedance of the top/air at a lower amplitude.
The cuts in the violin bridge allow it to flex in a number of ways, producing resonances at various frequencies. It's a tuneable filter, enhancing some frequencies and cutting down others. Trimming the bridge alters the mass and stiffness of the various parts, changing the filter characteristic, and helping to shape the overall sound of the fiddle. Problems with this can cause 'wolf' notes.
The arch top bridge is, by comparison, pretty simple. It needs to have enough mass and stiffness to provide a strong impedance mismatch with the string at all frequencies so that the string will 'know' how long it is, and what note to make. Since the guitar string is not bowed a guitar 'wolf' typically manifests as a 'short' note, one that's twice as powerful for half as long. A massive and rigid bridge helps keep that from happening. On the other hand, a lighter weight bridge tends to produce a more 'treble' or 'bright' sound, so you can use bridge mass as a way to 'tune' the response. I've seen no advantage in changing the flexibility of an arch top guitar bridge, although it can be artistic.
I'm not sure that the contact area of the bridge of an arch top with the top makes a lot of difference. You certainly do want to see that the bridge feet are well fitted. I have not done a lot of experimenting on this, but my experience mirrors the consensus view that a single foot is better on an archtop, rather than the two-footed bridge of a fiddle.
The tail piece on an archtop can also get into the act. D'Aquisto said, in a talk at a GAL convention long ago, that he could get pretty much the sound he wanted by changing the tailpieice. It's mass and length, and the way it's pivoted, all make a difference.
Arch tops give you a lot of knobs you can twist to adjust the sound after it's all together, and it would take a long time to explore the whole space.
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