Doc Eastman

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About Doc Eastman

  • Rank
    Member
  • Birthday 04/06/1946

Profile Information

  • Gender
    Male
  • Location
    Mt. Shasta, CA
  • Interests
    Traditional music
    Instrument making
    Skiing, windsurfing, fishing, hiking
    Good wine
    Medicine
  1. I know that you asked this some time ago but I just noticed it today. I believe that the Saconni measurements include the platform BEFORE the purfling channel was cut. After the channel was cut these measurements would have been slightly less. BUT if in doubt always leave the edge areas thicker, especially through the C bouts. You really do NOT want the loudspeaker effect. Some stiffness is better

  2. Correct. This was difficult for me to grasp when I started! I was taught to express this angle as 6.5 rather than 90-6.5, but have seen it both ways. I set the protractor at 83.5 however. Expressed either way, when the neck is fit to the block the face of the neck (may not be using the correct terminology) is usually about perpendicular to the ribs. As mentioned previously, I do not use this angle to fit the neck, using the projection of the fingerboard onto the bridge (fit to the top and in the right position)to determine the angle of the mortise. Once I make the cut in the top 7mm from t
  3. I was taught and to measure 7 mm in from the top edge (so neck from lower edge of button to top end of neck is 137 mm), measured in the midline. If overhang is 2.5 and rib 1.2, then the cut extends 3.3 mm into the block at the midline, less at the edges depending on the curvature of the top. I was also taught to cut the angle of the neck root at 5.5 degrees, which meant that the mortise was a little deeper at the button, in order to achieve the correct neck angle/projection onto the bridge. I now cut the angle at 6.5 degrees and the mortise is about the same depth top to bottom, but do what
  4. I posted that good maple for ribstock is not available to match the back. However, a cello neck block is a good source of rib material if you have a bandsaw setup for resawing thin slices. I just set up my Grizzley 14" saw with a 3/4" blade (not the carbide imbedded type) and was able to saw thin slices (1.5mm) from leftover pieces of a cello block. If you want highly flames ribs probably better to buy them directly (int. violin, for example sells highly flamed finest-flamed violin sides for $33/set, and nicely-flamed for $6.50, other suppliers may have better prices). In contrast, a sligh
  5. Have you tried an instrument cleaner/polisher compatible with your finish? Depending on value of he instrument, I might try french polishing (rubbing with a soft non-abrasive pad) with olive oil, and depending on the finish state a slight dusting of very fine pumice (I rub out all my finishes with this method). Could also use mineral oil i same way. If it is a fine instrument I would take to a luthier.
  6. Does the varnish smell or the cavity, or both, if you can tell?
  7. BA survey was carried out on wood workers and on a group of unexposed, healthy controls. One group of wood workers (group A) were asymptomatic and another (group had symptoms either of chronic cough and dyspnoea on exertion (B1) or dyspnoea at work and bronchial hyperreactivity (B2). The control group (group C) was randomly selected from among a population of laboratory workers. No significant differences were found among the groups with respect to the frequency of atopy but the prevalence of a positive skin reaction to wood extracts was significantly higher in the asthmatic subjects. The adj
  8. Since so many people in a field of interest have real or perceived conflicts of interest, the approach in medical research is for everyone involved to file their conflicts of interest in writing, so they are available to people who review the data, publishers, and people who read the study results. If someone has a vested interest (stock holder, or could otherwise materially benefit from the results), they should be excluded from any critical vote or result. In clinical trials they usually leave the room during critical discussions and voting, as their very presence may bias other participan
  9. Internationalviolin.com provides pre-cut and thinned rib stock for violin, viola, cello, and bass, matched to the maple back. They give you enough extra that you can afford to waste some learning to bend. Not directly related, but it is much easier to bend ribs on a bending iron if you have a piece of lead sheet (rib is between sheet and iron) that distributes and holds the steam better and reduces break-out. I have opted for this because stock matching the back is not available. You can resaw a maple board, but you need a good bandsaw and a wide blade (3/4")for rewsawing. My teacher uses
  10. Sx only very late. Elevated blood calcium and high 25-OH-vitamin D level(25 hydroxy vitamin D is made in the liver from dietary or UV converted cholesterol). Both are biologically inactive. The active metabolite is 1,25 -OH vitamin D. the second -OH is added by the kidney. 25-OH vit D level is routinely available and the best test for both deficiency and vitamin D intoxification. Levels of about 30 are considered normal (with the societies recommending 20-30 as the optimum for general bone health). Not unusual to see levels of 50-100 in people taking 4K. If you get some sun exposure it
  11. We have been speculating on the time difference and wondered how many cups of coffee you were working on. Sleep well!
  12. For those who don't look at audacity FFTs, softer is more negative. So -30dB is louder than -60dB. So violin 1 at -30dB - Strad at -60dB = a point that plots at + 30dB (-30-(-60)= +30)above the zero line on the plot, or louder on the violin 1 (modern) side. Gee I hope I have this right..algebra happened many moons ago.
  13. I think you mis-typed d#4, as d#5 is 622Hz (at least according to my Wikipedia table...).
  14. Anders, please clarify the difference spectrum. I am assuming that you are plotting modern dB-StraddB, and that anything above the 0 line on the graph, in positive territory, is louder.. Perhaps I have this wrong.
  15. The modern is louder in the low end, with a big difference around C#4, where the strad is softer (hard to tell on a log scale however, Anders???). Is this the difference people are hearing? This could be very dependent on sound post placement/setup. Might be possible to set the two instruments up to have identical spectra, then test them for differences that are not apparent in the spectra (concert hall from back seats... )