Mike Atkins

Little by little, as I've had a chance...I've been building all the things for my 1690 Tuscan model. I still have to make counter forms for gluing the corners, and maybe even one for the center bout bending...I even made corner templates to help me get an eye for how to do it (about 1mm longer than the actual Tuscan corners), and a drawing to check my work against and mark measurements. This is actually like the 3rd form, and about the 8th neck template, because I keep tweaking them...but I'm excited to start using them. I love that instrument, or maybe I love more that I have so much info about it from the book. Hopefully after I make a few...dozen...I'll have a decent one.

Yes, I agree with you, and what you originally note. I think we perhaps use sub-millimeter precise measurements because that's what's available for the instrument in its current state, and we can't know much more except how to replicate it as closely as possible? Where originally such sub-millimeter measurements might not have been so carefully attended to... So the sub-mm is maybe a modern thing to a degree. But certainly it makes sense that for the most part there's somewhat of a difference as a result of tampering and time. It's sort of two things going on at the same time. As I understand it at least. But I would say for sure if 1 block is 32mm, and another is 29, they likely didn't both start at 32.

I'm sure things get deformed of course and weird... I guess what I meant was if the block heights were all originally 32mm high, I'm not sure we would see them at around 29mm now. 3mm is a ton of wood to remove or height to lose from compression of a strung up instrument, or from opening the instrument a few times...at least it sounds like quite a lot. How much could block heights change? and if the blocks are close to original, wouldn't rib heights at the blocks be pretty close too? I'm genuinely asking because I don't know.

I actually saw your video where you were making compass marks to trace your cello form outline, and that was actually what led me to theorize about it. But your right: Particularly MS2, MS11, MS205 I probably shouldn't get into these discussions either...you're wiser than I am!

You're absolutely right about this, and I thought about it and imagined it could be scraped away or made nearly invisible like the centerline on the scroll fluting, but that was probably presumptuous of me. I keep finding new theories because it's fun, but there are definitely issues like you mentioned. The neck heel is an interesting one though...and one that wouldn't be necessary today so perhaps not often considered?

Really beautiful work. I agree the upper dovetails look odd, but when the lid is closed it looks like they would perfectly match the dovetails below it?

Earlier in this thread, I made a suggestion about the use of the arcs on Stradivari's forms that probably doesn't make sense without a visual reference...this graphic perhaps clarifies things for anyone who might be interested. Of course I can't prove this—and it's probably wrong—but it seems a practical, bench top solution to specific challenges. The shape of the top block creates three problems that seem to need a solution (particularly for a baroque, nailed on neck): Marking the purfling groove on the back by the button can't be done with a tool, so you need a radius to mark the channel A nailed on neck cannot have a squared end where it meets the ribs, it must have a radius A nailed on neck needs an additional radius for the overhang of the top plate

This is a quite reasonable question, and could certainly explain the seemingly random rib heights for sure. But only if an instrument has been repeatedly tampered with. I believe certain ones haven't been messed with as much as others.

It's clear you're very committed to your theories, and far be it from me to put a damper on your passion. I find what you're saying unconvincing, but It seems the arcs are a rather trivial thing to spend more time debating with you. So I'll just say again what I said before...I could be wrong.

Because the radius changes when you add 1mm thick ribs, or when you need to notch out a second radius on the neck block to make room for the top plate overhang, or if the purfling channel requires two marks. If it's not defined by standardization, can it still be defined by tradition?

I agree with this in particular. But I don't think a reference would be needed for making forms or meeting strict proportional requirements, I think the practical necessity of churning out salable instruments and feeding 12 or more kids, would have been more pressing. What do I know about their motivations though? If I had to radius a neck heel to match the curve of the top block, I would mark it on the form. If tradition insisted that 32 was the magic number, I would mark it on my bench. But what do I know?

That's certainly true, but I'm not sure that's what I'm doing, certainly not what I'm trying to do. I'm asking why the need for such a reference mark, for a standard you specifically state is defined by tradition with margins, specific to each form? Rib height is not really form specific or is it? The radius of the top block, is form specific, right? "They fit reasonably well" was what you stated, and that's correct. But that doesn't confirm block/rib heights are what the arcs are for does it? I found it odd when reading Sacconi's book where he proposed it.

Like I said I could be wrong, and usually am... However, I guess I was referring to actual rib/block heights....that range, in this example from 28.9 to 32.1 mm. This doesn't seem to vary much across instruments, but they certainly don't match a particular height even from corner to corner. They all seem to be in the same range regardless of form being used. So why mark such a reference for something fairly standard like 30-32mm on the form as though it's unique to the form? Particularly when there are real problems to solve like purfling at the back button, or the neck heel radius where an arc would serve a practical, form specific function?

I do find it interesting, but it doesn't preclude making copies of the form and building on them. I like to think they had a more practical function like I suggested, but who knows? certainly not me. Where I struggle with the "rib/block heights" idea, is that from what I can tell the ribs/blocks never correspond to these heights, nor does there seem to be a noticeable difference in the heights from one instrument to the next which would require a reference...I could be wrong of course. I also think having a radius for the neck heel is something no longer relevant, but would vary based on the shape of the top block from form to form. ¯\(ツ)/¯

For some reason I thought I could carve the radius into the cradle with the sides still on...of course I took a chunk out of the edge...but, the fingerboard fits nicely in the cradle on both sides, in spite of the mess-up. I suppose I could make a new side if I needed to, but this is a jig so it doesn't matter too much.