Kevin Kelly

Members
  • Content count

    149
  • Joined

  • Last visited

About Kevin Kelly

  • Rank
    Member

Profile Information

  • Gender
    Not Telling
  • Location
    Boston, Massachusetts
  1. Input needed colophony + nitrocellulose?

    I don't know anything about those things, but from the photos it looks to me like heavily stained plywood with some thick, quick-drying glop brushed over it.
  2. J. Curtin Viola Design "Evia"

    Here's the viola from Tarisio compared to an Antonio Amati.
  3. Violin geometry references

    I have a system that I use to make new instruments and to help me understand the design of classic violins. The “Four Circle” thing is a central part of this system. I’ve shared some bits and pieces of it, but I think that maybe only leads to confusion. I think it’s probably time to write it all out in a way that I can present it clearly. That way, if there are people who are actually interested, they can see how it all works (in my head) and then see what they think - there’s a lot more to it than I’ve posted so far on the net. I have over 10 gigabytes of drawing files on my laptop at the moment… I don’t think anyone wants me to drop them on MN I’m thinking of maybe a pdf booklet… it would take a few months probably to do it right, but may be the way to go.
  4. Violin geometry references

    All's I'm sayin'.
  5. Violin geometry references

    Hi Ben, Over here we've been busy with Thanksgiving for a few days, but now I'm back... These are fun exercises to do, but I think I may be getting these viols mixed up. https://youtu.be/cMUdM0puaHc
  6. Kimmo, If you want to see the sound hole layout drawings, you can get the Pollens book, or you can more easily get the book that Ben mentioned, the recent catalogue from the Stradivari Museum http://www.museodelviolino.org/en/nuovo-libro-antonio-stradivari-disegni-modelli-forme/ This is an excellent resource, and has images with measurements of all the pieces that are in the Pollens book (you have to have both the book and the cd that goes with it to be useful).
  7. Violin geometry references

    Just for fun... from my perspective. I don't have the same historical outlook as Francois and Ben, but I spent some time looking at Ben's viol this weekend and I thought I'd show how I would approach it, if I had to (at least to start). https://youtu.be/YXYS-7WIHtw
  8. Violin geometry references

  9. Violin geometry references

    OK, how about this? You want to use a violin bridge template for a violin, cello template for cello, etc. and you may want to make the string heights higher or lower for some reason, etc. The template is already done because it’s been figured out how it works, and you can make whatever modifications you want and make your customer happy. What i use is exactly that - a template that can be modified, so if you want to make something different you don’t have to start from scratch each time, and the result will always look “right”. I'm moving my studio, so I can't take photos of stuff right now, but here are a few fiddles I made. Can you tell these shape were drawn with a compass?
  10. Violin geometry references

    Some thoughts about this thread, in no particular order - The video that was linked to above was made by me some time in the last few years in response to an irritating discussion on MN, actually, and I think the point I was trying to make was that any discussion about this kind of thing is only relevant if it can produce a usable, useful result, in the real world, and that if you can’t prove that it works in real life, you should maybe not claim that it does. Since then I’ve tried to avoid the topic since it seems to antagonize some people (especially me). Not that I have a problem with it, but the Strad did not ask me nor tell me about posting the video on their website. Actually, I thought that I deleted it shortly after posting it, and was surprised to see it still around. If I’d known they were going to use it, I would have put a little more effort into it. Marty has published some work on violin design, but for some reason he seems to have forgotten to include himself in his list earlier in the thread. I really hate the word “geometry” in this context, because its modern meaning is confusing to any discussion about violin design. Any reasonable amount of reading on the subject would make it clear that Francois is correct when he says that in the age of Andrea Amati “geometry” was nothing other than measuring. Nothing mystical, and not really anything to argue about. The fact that there have historically been so many bad hypotheses about a specific theory or system doesn’t mean there wasn’t one - there was. I disagree that theory doesn’t matter to modern makers. It may not matter to all makers, but I think it’s exactly like saying that music theory doesn’t matter to musicians - they can learn to play by ear, so why do they have to bother with all that theoretical stuff? The way we all learned to make violins is like playing by ear. “Here’s a thing - copy it. Why does it look like this? Well, that’s just the way it’s done.” What I want is violin making theory, so that i can understand the forms I’m making and change them if I want, and still make something that’s traditional. I feel like it’s respectful to do that, and it gives me a feeling of freedom to make whatever I want. I like it when someone looks at an instrument I made and says - “Amati?” or “which del Gesù?” Finally, here’s what I’m working on right now. I recently decided to make a “copy” of a del Gesù violin (not a real copy of, but based on, a really nice fiddle). I took some measurements from said fiddle, plugged them into my little system (just like in the above-referenced video), and, using proportional dividers and a straightedge, drew a template for a mold (again, following the Andrea Amati recipe in the video - very simple). Here’s a picture of a quick tracing of the template with and without a washer to draw the edge, laid over a photo of said fiddle. Now - does anyone here want to tell me that I don’t know what I’m talking about?
  11. Perpendicular does not exist on violin tops...

    At the risk of opening a can of worms, I think that the concept is much simpler - it's that the bridge divides the angle of the strings over the bridge. In other words, if you were to draw a line that divides the angle that the strings make when they go over the bridge in half, that line should go roughly down the middle of the bridge. On violin this almost always works out if you make the back of the bridge perpendicular to the plane of the ribs, but that's a result of the given parameters, not a parameter itself. That's also as far as you can lean it back without it looking very scary. If the force vector of the strings is not contained entirely within the bridge, it will be guaranteed to warp.
  12. Casein glue and ground

    Berl, When I worked for Roland Feller in SF he told me that at Wurlitzer's they used Borden's white glue to glue in cleats, but that was before they changed the formula. My understanding is that it used to be casein glue, and now is some kind of plastic.
  13. Digital Amati project

    Hi Torbjörn, I don't know about the first question, but I'm sure it's possible. I don't use the outline function myself. As for the second one, no way. I'm all done with the video demonstrations. I did have Harry nearby to show me how to use it, though, and that really helped. I will admit that at first I was not interested in doing so, but I'm glad I eventually did. I agree. However, in the end the geo engine does the same thing as a divider and straightedge. It just saves a lot of time if you do a lot of drawings.
  14. Digital Amati project

    I should say that the Geo engine is easily one of the most important and useful tools that I have. It may not be for everyone, but if you can manage to figure out how to use it, it's a powerful game changer.