DW & All,
First, for clarification, Lance, I may well have corn-fused issues misspeaking "in" versus "out" flare in haste. Correct me if wrong but inflare ("in" being medially) swung, or outflare ("out" being laterally) un-swung or to some degree "bunionized".
As to matching customer's foot shape to last shape, yes, I have a digital "library" of last models that range from max. swing (U.S. NAVY) last 1930s and others that match that degree of swing, lots of "neutrals" like my 1930s West Ender, and the all too common toe biting "outflare" shapes. First stop for me is seeing if I have a last model already that will fit the customer's foot shape re swing--I usually do.
When I saw into wood it's only to make a master turning model to have scanned, and I do this very infrequently, but Marlietta asked "how?", so I said. Let's say I get a really sexy old vintage last that I like in every respect for my "library", except it's obviously going to be a toe-biter (toe centered too laterally), I saw into it, swing it to match a known bottom paper ("neutral"-ize it, or inflare it), and send (or used to) it off to Tippit to scan, then order from that. In fact it was Bill who taught me the sawing and wedging technique. This swinging with saw cuts is used on the *model*--not the actual last.
What I omitted describing was how to find the tread-line on the last bottom for the saw cuts: take a piece of paper, make a heavy black area with a China-marking grease pencil; prop the last up to heel-height on a pre-built loafer heel or what-have-you; then rub the last's tread-line area side to side over the blackened paper, rocking the last to get a rub-line across the bottom feather-line to feather-line--voila, there's the last's tread-line to saw into from either side.
If you're going to charge "Mr. Smith" for a truly personal pair of custom lasts, why not swing an old "orphan" last that's close, to make a model (adjust girths and profiles), have that scanned then have a new pair turned for him and charge him "full freight"? *CHA-CHING* (U.S. slang for making money) IMO those custom lasts might still require fitting up for the larger girth foot, or a "blister" of leather here or there, but they shouldn't be some monstrosity--no matter how beautifully executed--created out of layer upon layer of leather shelling some poor little butchered last inside, especially seeing how fittings refuse to stay stuck to plastic lasts. Weigh this: what's better, spending hours gluing, skiving, sculpting and sanding leather scraps on a pair of lasts to sell (once), or fitting-up one single orphan last to the smaller foot, paying to have it scanned, and a fresh pair turned 1:1 ?
Since I won't be able to see all the pix you're discussing until I get into the office, I have no comments there except, I'm stumped--"strick point"? Please 'splain it to me Lucy'. In feet with depressed transverse met. arches, how do you locate this "V" point? Where it ought to be in nature? How?
DW, for one-offs, custom bespoke jobs, you're fine leathering-up your forepart/toe medially to increase swing; however, if you have a favorite last that ALWAYS requires a medial forepart fitting to not clip most any "neutral" foot (avoiding toe-biting), I'd say that last needs to be swung and a new model made. Thirty minutes with a saw, wedge and glue once, then have it scanned and future lasts made off of that improved model would save you a lot time and effort, as it will reduce the medial build-ups you'll need to do to it in future. Bear in mind, all of these tweaks are just like vol, bass, treble, mid-range adjustments on a hi-fi, just dial to suit your taste and acoustics so to speak.
Like you, I "follow the foot", and plop successive lasts/bottom papers on a customer's tracing/imprint to select either: 1) a last that already fits in bottom profile shape (swing), to build up to girth, or 2) to pick one to drastically modify in those rare cases when a scratch-made pair of custom lasts are indeed required. I'll copy off the ink imprint and tape it to serve as a template to the last bottom while rasping/grinding. While I enjoy fiddling with lasts, sculpting, re-modeling, etc., I admit I hate doing leather fittings, especially on these non-stick plastic lasts.
And I think Dan "El Jefe" Freeman was perhaps quoting John Henry Thornton with the three-legged stool analogy he gives in the intro to 'Textbook of Footwear Manufacture' --the 3 legs for him were: materials, methods, and intended purpose/function. When the forth leg, "fashion" is introduced, the stool can get mighty wobbly on uneven surfaces, and I tend to agree.
Finally, I'm sorry if any of my posts have sounded "preachy". You've been making boots successfully as long or longer as I have, and have developed your own method of fitting feet that works for you. I'm not suggesting you alter a thing. I have noticed over the decades we've known each other, you are very Teutonic! You like to reduce things neatly to "rules", systems, and formulas with lots of analytical math. I'm more "by eye" when it comes to things. As long as it slices, indeed, who cares how the knife's sharpened
That said, of course there is a need for precision on our work, and when communicating amongst ourselves some basic vocabulary. But let's not lose sight of the vastly divergent backgrounds here, nor the idiosyncrasies of the people, as far flung as we and those who trained us are, right round the world.