Felefar

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About Felefar

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  • Location
    Norway
  • Interests
    Looking ar rocks, and fiddles, and other interesting stuff

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  1. Because the wood in the top is chosen for acoustical properties, not for beauty or longevity. There are many woods which look nicer and keep polish better, and are also less prone to cracking. But they don’t sound good...
  2. That has been done: https://en.m.wikipedia.org/wiki/Vebjørn_Sand_Da_Vinci_Project It should really have been a catenary arc, which is much easier to construct than to calculate: All you need to do is trace the curve if a chain, suspended from both ends. Mr Sand decided to depart from the original drawing so much that I wonder hiw they could call it the da Vinci Project. From what I have seen violin arcs are rarely catenary and maybe even more rarely circular
  3. I confess that I am baffeled, nay flabbergasted, by this recent «Leonardo’s bridge» hype. Look closely at the original sketch. Then at the CG design. Are they the same? Does every curve match, or are they even remotely similar? Did Leonardo specify the shapes of the stones, or are they a modern approximation? Did he really propose to build a bridge across the strait of Bosporous using stone blocks weighing in excess of 1000 tonnes?
  4. Thorval H(or K) Fouxemberg is what it looks like to me. I can't make the first letter of the surname be anything but an F, the next letter is o or a but most likely an o; the third is an overlined u. The following x being slighty larger than the rest is not that uncommon. E and m (or n) are hard to make out but I think it's -em-. And then probably ending in -berg. The -d at the end of Thorvald is silent in most dialects, so it was not uncommon to drop it. Very many names had a lot of "alternative spellings" in the 19th century and before: Torval, Torvald, Thorval, Thorvald, Thorwal, Thorwald, and even Thorwaldh are known spellings. Not likely to be Swedish, very unlikely to be Norwegian, possibly Danish, most likely German.
  5. Maybe Guillaume in Brussels? Or Schmidt in Dresden - those two were the first I thought of.
  6. Oils and resins are really fatty acids, so adding lime leads to saponification. Saponified oils and resons have drastically different properties than the raw fatty acids, although not as much as simpler fats like e.g. palm oil (look at your soap, it will most likey contain sodium palmitate, which is the reaction product of lye and palm oil). Calcium soaps tend to be hard and practically insoluble, which is just what we need for varnish. Addendum: Aqueous solution is not needed to call an organic acid an acid, it is enough that the formula contains one or more COOH groups.
  7. In from the sidelines of not knowing anything at all - what about the old integral bass bars? They were used for a very long time, and must surely have worked well enough? Was there a standard thickness for those too?
  8. What about compressional anisotropy? Is the Lucchi meter always used to measure speed of sound along the grain, or are users sloppy in the directionality? Speed of sound is one important measure in my work (oil geologist, specialising in wellbore log interpretation), and velocity anisotropy is one of the things we always have to watch out for. We tend to state velocities in microseconds per foot, one of the very few non-metric measures we can’t seem to get rid of.
  9. I suspect that many experts decide on whether or not it is pernambuco or merely brazil wood by the general quality of the bow - if it is a good bow, it is pernambuco. If not, it is brazil wood or "fruitwood". I have a very pale L Morizot bow, very thick, and a very dark (almost black) slender L Panormo bow. They are both pernambuco, according to the experts.
  10. Cut it out on good 100g/sq.m paper. The weigh the paper on a precise scale. 1 gram is 1/100 square meter or one square dm. 0.01 gram is one square centimeter, which is about the limit if resolution on this. Before modern computerized nethods, mineral distributions in thin sections of rocks was determined in a similar way, using tin foil instead of paper. When I was a young geology student I printed photos on thick photo paper, cut out all the grain shapes and sorted them according to mineral, and weighed the heaps. I only did this once, to prove that my alternative computerized version gave the same result, but it still works for a one-off - at least on simple shapes. Come to think of it, good tin foil would be better...
  11. Furniture makers (at least in Scandinavia) use steam forming, steaming the wood under pressure and then bending it to shape. I imagine that is a bit of the same as using an iron, except that the steaming is done in a separate step?
  12. They do. Wood shrinkage and expansion with changes in humidity have to be taken into account when building any large wood construction. Space needs to be left in for differential expansion.
  13. Dutzenarbeit is the work of a dozen makers, each specialising in one component as opposed to one maker making every part himself. It does not necessarily mean lower quality.
  14. I'm planning a trip to Voss to show it to a fiddlemaker, as luthiers don't know what to make of it.
  15. This one rings on all tones, on all strings, and changing the tailpiece made no difference. I have decided to try to sell it to a fiddler who wants to avoid the hassle of tuning nine strings on a Hardanger fiddle.