mrbadger

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About mrbadger

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  1. It's not aesthetic vs. artistic. Rather, aesthetic vs. practical. In any case, the hand work has a vital function in violin making for a very practical reason. Stiffness increases exponentially with change in thickness. All those tenths of millimeters mean a lot! And the sound character of a violin is largely determined by the wood character and the complex pattern of plate thicknesses. A hand process, by its very nature, produces complexities in thickness variation on a human scale. "Human nuance" as Toshio Odate says. Nobody can prove that this doesn't matter. And basic engineering principle says is does matter. And the ear says it matters.
  2. Well, a historian of the period may well have an answer or provide some valuable context on how widely knowledge spread through the population at the time. (Cremona is a special case in that the history of Western civilization has an important nexus point emanating from there. Doubtful if that matters. But certainly it was a cosmopolitan place.) In any case we are not talking about "common craftspeople." More likely a polymath genius.
  3. FYI: Here is an excellent example of post-modern arrogance. The age of Stradivari saw the most far reaching advances in the advancement of reason, science, technology, mathematics, philosophy, etc. And historians identify northern Italy at the time of Stradivari as an early modern society for a number of reasons, especially the spread of literacy.
  4. The Belgian coticule water stones (6000-8000 approx grit) from Dictum are the best I've used. They cut very fast and wear less than the Japanese and others.Yes they are expensive. But not a huge investment for something so critical. These stones have been used since Roman era and are considered best for surgical knives. https://www.dictum.com/en/sharpening/bench-stones/belgian-bench-stones/705555/belgian-whetstone-block-250-x-60-x-25-mm?ffRefKey=TfvIH9uLX
  5. I'll use isinglass glue <<https://en.wikipedia.org/wiki/Isinglass>> occasionally for repairing cracks and difficult repairs. It maintains its full strength at lower viscosity than other collagen glues and so is excellent for penetrating cracks. It also gels at lower temperatures and so provides a longer working time for difficult gluing situations. Also stronger than hide glue. It's very expensive for a glue. 12.5 Euro for 20 grams at Kremer, Germany. Kremer, US, apparently no longer carries it. I keep a small quantity on hand and use it very sparingly only when needed. The true isinglass comes from the swim bladder of the sturgeon, an endangered species. Kremer, however, uses swim bladders from farm raised sturgeon used in caviar production.
  6. Or you could use a hand saw and a set of optical comparitors.
  7. On a wood lathe the tool is supported by a tool rest in front of the turning spindle. The work needs to turn toward the rest, and supported tool, or the tool flies uselessly off the work. Metal lathes are a different animal entirely. But for wood lathe with a hand-held tool there is only one direction that works.
  8. "Molecular Rheology of Coniferous Wood Species" describes the mechanism in which the three part system of cellulose, hemicellulose and lignin regulate and store the transmission of energy from bending forces, while maintaining a memory of those reactions. The published version is a little different from the online pdf but the basic information is there, minus some illustrations, But describing a mechanism is different from being able to measure changes. The human ear/brain system perceives sound with a sensitivity that is astounding and still unexplained.
  9. "Rheological behavior of wood in directions perpendicular to the grain," A. Ranta-Maunus, Laboratory of Structural Engineering, Technical Research Center of Finland. (Materials and Structures, 1993, 26, 362-369.) "Molecular Rheology of Coniferous Wood Tissues," S. Chow, Department of the Environment, Canadian Forestry Service, Western Forest Products Laboratory, Vancouver, British Columbia, Canada. (Transactions of the Society of Rheology, 17:1, 109-128, (1973)
  10. Materials science and rheology offer valuable insights into the various deformation and creep properties of polymers and of wood. The observed changes in the cellulose and lignin molecular bonding related to repeated stresses (such as vibrations) easily accounts for the "playing in" phenomenon.
  11. My asking whether people like hand work seems to have unleashed a lot of "us vs them" talk in regard to machines vs hand tools. It need not be that way. I probably have as many, or more, power tools as anybody on here. Six or seven routers, jointer and thickness planer, drill press, table saw, mortising machine, chop saw, etc. Even a small molding machine. They all have a place ... . .... Just as hand work has a place ... especially when it is as enjoyable as violin work.
  12. Purfling routers Carving duplicators CNC machines ... on and on. Do people really not enjoy the hand work?
  13. On the ammonia treatment issue. Yes, ammonia has been used to darken wood (especially popular for white oak in Stickley and Craftsman furniture). It's a fuming process. However, ammonia is also used for industrial wood bending. Fuming wood with ammonia soften the lignin and allows wood bending without the heat and/or moisture. Since this is anhydrous ammonia, however, it's not a small shop kind of technology. Since it softens the lignin, however, it likely has a de-damping effect on the wood, relieving and inner stresses left over from milling and drying. The soaking and careful drying likely does the much the same. Although the ammonia fuming would be kind of like taking a sledge hammer to a finish nail. Careful drying an a bit of age does the work much more gracefully.
  14. Yes, I vote for this as well. I was first shown this method (as a general technique) by a furniture maker who explained that this "initial tack" property of hide glue is one of its primary advantages over the various synthetic glues. That and its reversibility. (Newport highboys, for example, use pressed in blocking in several locations.) I'll use the finger-pressure clamp in many such situations. A little patience saves a lot of head scratching over clamping cauls and direction of forces. Although they have a place as well.
  15. The question is interesting because it gets the divide between subjective experience and objective measurement. You can look at this as a continuum of relationships. One side, for example, you have a clean correlation of subjective experience and objective measurement. We perceive a color as blue; the wavelength of the light falls within a specific range. One the other end of such a continuum you have a subjective experience of a "great" violin vs. our ability to measure what causes that. The later subjective experience is colored by a host of acoustical properties, as well as our biological and conditioned responses. Finding clear and objective correlations that account for the experience has proven to be daunting even for modern science. Note however, that even on the simpler side of the continuum, there is a problem. Not everyone perceives blue the same way. Even those within normal range of color vision see the standard colors as having somewhat different relative values. The subjective experience vs. objective measurement relationship is a universal problem (or maybe celebration) of the human condition. The violin, I believe, is a primary example of the limitations in finding objective correlations to our human subjective experience.