Kevin Kelly

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About Kevin Kelly

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  1. The reason I posted this observation is simply that it shows a bit more about one artifact in a museum full of Stradivarian artifacts. I thought it was interesting to see how an artifact connects to a real actual violin. In this case, there is a written description referring to a particular type of violin (Amati “large pattern”) of a particular year, and I happened to have ct scans handy of a violin of that description. The strip of wood references thicknesses, but it doesn’t say what the thickness are, and it looks like it fits between the upper and lower blocks of that instrument. for me it is just an interesting thing to know, even though it doesn’t explain anything. This is just an observation of academic interest to me, and it is the kind of thing I would just notice and file away until something came along that looked like it might be connected, like the Stainer back. I still dont’ know what, if anything, it means, but eventually a lot of observations may lead to something interesting, if more people know about it. I don’t think it explains the secret of Strad, or that it has anything directly to do with violin design, it’s just an interesting stick that now has a bit of meaning that it didn’t before. Maybe I should have titled the thread “interesting stick” instead of referring to pins, but that’s what reminded me of it.
  2. There is another possibility that hasn’t been mentioned. My own theory is that the hole may have to do with centering the c bouts. There was a long thread about this several years ago that I can’t find now, where I posted some pictures of a jig I used when I was making “baroque” violins. I can’t find any picture of that now, either, and the jigs are in a box somewhere, but it was just a piece of wood, about 50mm tall and 140mm wide, and about 7mm thick or so. There were two slots about 3mm wide and 32mm tall cut into it at the distance of the ribs, so the jig slipped over the ribs rather snugly at the narrowest point of the c bout. In the center of the piece of wood is a small hole that is drilled through, from top down. I made the jig because I was trying to emulate the process that Hargrave described. The system worked well, but I ran into a problem - using locating pins keeps the upper and lower blocks on the center line, but the rest of the ribs are free to move around, and are hard to corral when it comes time to glue things together. I wanted to keep the center of the fiddle on the center line as well, especially the part between the upper eyes of the ff’s. What I did was 1) drill a hole on the center line of the form at the narrowest spot (same size hole as the one for the jig) 2) with the finished ribs still on the mold, place them on the back using the locating pins and take the first outline for sawing. At the same time, place the gimlet through the hole in the form and drill all the way through the plank for the back, which has been thicknessed pretty much to the finished height, but is still just a flat board. Put your finger on the other side so you can feel when the point starts to emerge. 3) finish the back except for the final outline and purfling/edgework 4) take the ribs off the mold, attach the neck 5) place the ribs w/neck on the back using the center pins, place the jig on the ribs, slide the gimlet through the hole in the jig and rescrew the gimlet into the hole in the back that it made before. Now the upper block, narrowest point, and lower block are all on the center line, and will stay there while glueing up. This system works pretty well, but it doesn’t explain exactly the ventral pin thing. For one thing, the placement of the pin is not normally the narrowest point of the ribs. But maybe it could be that whatever jig they were using was designed to go wherever they decided the thickest point was going to be, as when you reinsert the gimlet there’s just not that much wood to hold it in place. It might also be handy to have a hole already where you’re going to measure the thickness from, so you don’t have to keep re-measuring it as you go. I don’t strongly believe that this is the reason for the pins, but I think it’s possible that it’s something like this. my idea may be some primitive version of the actual model. thought I'd throw it into the mix.
  3. Thanks, but I would say it's not that much of an insight, since it had a description written on it! I think I just spend more time looking at things like this than most people. One side-effect of not watching tv. That's what I think is interesting, it hints that the thicknesses are assumed, and just the location needs to be pointed out. Whether it was from one of the Cremonese workshops, or, as you suggest, by Cozio, it points maybe to a different way of thinking about thicknessing than I have. the stick is 320 x 14mm according to the catalog, no thickness is given. maybe Bruce knows, if he's reading this. I get the impression from the photos it's just a strip of rib stock or something. I agree that the string length is the starting point, the other things you mention I was not aware of, but that's why I posted it - i thought others might have ideas about it.
  4. I thought about posting this in the “rib taper” thread, but it seemed like it had gone far enough afield by page 15…. (edit: looks like that thread got picked up again as I was writing this) In that thread someone linked to this excellent post by Jacob Saunders that included this photo of an opened Stainer violin, with pin pricks along the center joint. That reminded me of something interesting I noticed a few years ago while looking through the catalog of the Museo del Violino. MS 995 is a stick with scratch marks and writing on it. It’s 320 mm long, and the writing says “thickness of the violin of Amati of 1654 large pattern” (I won't post a large image of it because I'm not sure the museum would be happy about it) Of course I had to clean it up a bit and take a look at it compared to a “large pattern” Amati of 1654. This was made easier by the fact that there happens to be one in the collection of the Library of Congress that is in the public domain. the yellow lines are lined up with the scratch marks on the wooden strip as well as I could this image is a composite of ct images of the back, front, and sides of the "Brookings" Amati of 1654 You might notice that the pin in the back closely coincides with the "x" marked in the middle of the wooden strip, while the first yellow line is at the bridge location. Not sure what any of it means, I just think it's interesting.
  5. I don't know, but, Sacconi did say in his book that his observation was that the bridge was always placed at the balance point of the top in Stradivari's instruments, sans bar. He wrote that he thought the bridge placement and f hole layout of each model was determined by trial and error, and then cemented once he found the perfect position.
  6. As far as I know there are only five Cremonese instruments for which we know the original neck length. Two are tenor violas, two are small violins, and one is the Lady Blunt. I say this because four of them have their original necks still attached by their makers, and the Lady Blunt has its original fingerboard definitely associated with it. The Soil is another candidate, but it would have to be clear that the board is definitely from that instrument. If anyone knows about another Cremonese instrument where the neck hasn’t been removed and replaced (like the Amati tenor in Oxford) I would be interested to know about it. There is, as far as I can tell, nothing at all to tell us what the original neck length of any cello was. There are neck templates in the Museo, but those are all longer than they need to be, and there’s no mark to clearly indicate where the string ends or where the root ends. The five instruments are Stradivari tenor A. Guarneri tenor Lady Blunt Bros. Piccolo Del Gesù quarto Add to this the Soil if you like. This list spans about 120 years. The violins, in spite of their different sizes, have kind of similar neck lengths, in order: 120, 118, 119*, 118 (* I don’t have a quality measurement of this neck, but it’s close to that) The two tenors have similar neck lengths, at 156 and 158 If I were to look for a relationship between neck length and some other aspect of these instruments, there are two possibilities that I can see- stop length and body length. If we exclude the two small violins, the ratio of neck to stop length for the list above is (to two decimal places) 0.60 Strad. Tenor 0.60 Guarn. Tenor 0.62 Lady Blunt 0.60 Soil The ratio of neck length to body length is 0.33 Strad tenor 0.33 Guarn. Tenor 0.34 Lady Blunt 0.33 Soil ( I have 356 for a body length measurement) So from this meager list it looks like either one is a possible direct relationship, but the body length maybe is a better match. It’s possible that they are both a match, because in these cases, the ratio of stop length to body length is pretty consistent also (which would have to be the case) These are 0.56 Strad tenor 0.55 Guarn. Tenor 0.56 Lady blunt 0.56 Soil The next issue is that the relationship of stop length to body length varies quite a bit. I have measured lengths that vary from 54.6% to 56.3% for violin, and 53.6% to 54.6% for viola and cello. Interesting that there are two ranges. So what I notice is 1) we have a very tiny sample size, 2) that sample size is uncharacteristically consistent in the ratio of stop length to body length 3) guessing from the sample, it’s possible that the stop length, body length, or both (or none) could be used to find the neck length 4) it’s not possible to have "both" be true for most Cremonese instruments. If the stop length or body length were used as a reference then it would have to be one or the other. my own guess, for the above and for other reasons that have to do with my own bullshit, is that it’s more likely that the neck length may have been related to the body length, and not the stop length. my opinion is subject to revision without notice...
  7. Yes, I understood that - my comment wasn't in response to you, it was just a general question about whether one should expect to find some particular ratio of neck length to stop length in the original Cremonese instruments the way we expect to see in modern instruments, especially, as you point out, the stop lengths vary quite a bit. Does that mean many different neck lengths for many different models of violin? Maybe it did. Just an interesting question. Thanks, by the way, for the information about the Soil fingerboard. I wonder how confident you are that it goes with the Soil?
  8. Davide is right, of course, but it's still interesting to speculate. My question is whether the idea that there should be a direct relationship between neck length and bridge location isn't a modern assumption that may not have been true for Amati or Strad. I suspect it may have been more complicated than that. Also, I've made several baroque violins over the years, using Hargrave's technique, and have found it to work just fine. I find his analysis to be brilliant, including the little hole in the pegbox, etc. I added a way to keep the c bouts centered on the center line as well, but the method he describes works, and is very fast. I see no reason to question his theory, so far as it goes. If you take the time to center the neck root carefully then you should get a pretty symmetrical outline no matter which method you use, but if the neck is off center then things get more interesting, and the method shows itself - take the Conte Vitale as an extreme example. ps. long ago I stopped nailing necks to violins, after I had to "modernize" one of my baroque violins that had a nailed-on neck - what a huge PITA that was.
  9. Hi David, If a template or system helps someone get where they want to go, or understand things better, then by all means go for it. I’ve done lots of that over the years, and changed my mind many times, too. My point is that I think looking at cross-arches that way is looking at an effect, not a cause. I could be wrong, you know, Sacconi wrote that Stradivari used arching templates, and though I disagree with that, he knew a lot more about those fiddles than I do. I find it hard to write about this kind of thing. There are too many variables to even figure out where to start.
  10. This discussion is about cross-arch shapes and ways to make templates for them, but to me the question is whether the cross-arch shape is important or not? It’s not really something I think about when making a violin, other than I want the arch to look good. in the 90’s when I had a job teaching violin making I showed the students how to make and use cycloid templates, which I still think was a useful exercise for a lot of reasons - but I don’t use them myself. I noticed, as others have, that if I just carve the arch I want to carve then cycloids will match pretty well when I’m done. In my experience that’s not unusual. So is the fact that they look like that cause or effect? I don’t know about other theories, and I haven’t tried them because I don’t look at arches that way, or think about it that way. I know that I have a reputation for being obsessed with design, but I don’t think you design arches with measuring tools. I think you do it with carving tools. The difference for me between designing a body or a scroll template and designing an arch is that to get from step zero to step one in making a violin you have to design a body, a scroll, and an f hole template. In other words, you start with nothing and end up with something. If you don’t design it then you need to borrow it from someone who did, or you can’t make a violin. You gotta start somewhere, so the only option is to get your hands on a 2D design one way or another. when you’re shaping an arch, you start with an outline already, and a piece of wood - that’s a lot more than nothing. You could say that because we are making stuff, there is a continuum from theory to practice - they’re not totally separate. The question here is how to shape the piece of wood, and the answer as I see it has more to do with practice than theory. My two cents.
  11. Hi everyone, Some time ago, somebody on MN posted an image of an X-ray of the Stradivari Tenor in Florence. I've been trying without success to find that thread. Does anyone remember that and/or know who posted it? Thanks, and Wishing everyone good health - KK
  12. I'm not aware of any online source that has anything like the info on the poster. Personally, in your case I think €40 is worth it. A lot of work went into that poster by thoughtful people. You say you have a workshop and tools, so you should be able to swing it, if you want to try to do a decent job. Just spend the money. The poster has a lot of info that will answer questions that you have not thought of yet.
  13. For what it’s worth my own observation about cremonese instruments is that the plate that gets glued first is flat, and the one that gets glued second is tapered, so guitars, for example, where the belly is glued to the ribs before the back, have a flat surface for the belly and a tapered surface for the back, and a violin is the opposite. If I’m not mistaken, I think Roger Hargrave’s explanation was that the taper had to do with the neck set, which was not 90 deg., but more like 87 (or something). Placing the tapered rib of the upper bout flat on the bench (with a spacer for the edge thickness) and fitting the neck heel to that angle before nailing sets the neck with that angle. I’ve done it and it works. To attach the neck of a guitar, you place the ribs and belly structure upside-down on the bench, with an overhanging tongue of spruce sticking out where the neck goes, and place the neck upside-down on the tongue ( with a spacer under the rest), and fit and nail the neck to the rib structure, so the neck is in the same plane as the belly.