Don Noon

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About Don Noon

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  • Gender
    Male
  • Location
    Carlsbad, CA
  • Interests
    Acoustics
    Violin construction
    Varnish
    Old-time fiddling

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  1. Impossible to tell from here. If the soundpost is in a terrible spot, then maybe. If it's in the best spot, then no. Gotta find out by messing with it.
  2. It's all in the machine; I did attempt to align it at first, but didn't do a good enough job of it. Now I know more, and will do it better after I get done with these instruments. I see that now there are machines with linear bearings instead of the round rails. Far more rigid. If I can justify the upgrade, I would really prefer that.
  3. Still a lot of time spend in tooling and fixtures for the new models, but a major milestone was cutting a purfling groove and outline of a back plate. It was a pre-roughed maple blank, so the hold-down method was just for this one. I'm pleased with how it turned out, so far. Not obvious is a huge effort to fix a tiny problem: the CNC machine X and Y axes were out of perpendicular by ~0.3 degrees. With the garland made with that skew, and the back cut out and flipped, that would double the skew and the corners would be out of alignment by almost 1 mm... too much for me. After gnashing of teeth and racking of brain, I finally managed to reverse skew the model geometry, and that is what you see here. After this batch, I'll precisely align the machine and not have to go thru this again. And in case you were wondering... it is a torrefied maple back... which required me to cut apart the pre-carved blank, and then glue it back together afterwards.
  4. I know Manfio has posted that he uses 375 mm on almost everything (link). It's what I use on my 40 cm viola, which is the only size I make now... unless someone specifically wants shorter scale. However, my small viola is specifically designed to use a long string (i.e. short-ish lower bout, long-ish upper bout), so you need to think about that from the beginning.
  5. Greg S. is first and last responder, so it's all sold. Thanks.
  6. I would most worry about thin areas very close to the upper block, which might make neck projection unstable. It would be worse for steep arching in the area, and medium or low density wood. But in general, if it sounds decent and isn't distorted, I'd leave it alone. "Auction instruments" sounds like something more likely to have higher density wood, so maybe it's not a problem.
  7. A bit of shop cleanup, and realizing there are some things I will never use in my remaining time... High-clarity hide glue, 192 strength, from Tools for Working Wood purchased several years ago. Unopened 1-pound packages. Probably BT&C product. Absorbs water very quickly, and gives a very fluid hot glue with no lumps, and (like it says), very clear. I probably bought 5 pounds of the stuff, and this is beyond what I will ever use. 3 pounds available... $18 for 1 pound ($10 + $8 shipping), or $45 for all 3 pounds ($30 + $15) shipping. Also available are 9 old German-made bridges for 3/4 violins. One bridge has a wing nick, and some of the others have thin-ish feet that might require careful cutting (they were manufactured that way). They are at least 20 years old, as I know I didn't buy them in the last 20 years. $16 for all ($8 + $8 shipping)... or if you buy all of the glue, I'll include them for FREE!
  8. I can't imagine getting a good result with a hand-held power screwdriver. Drill press (or mill), good-quality bit (I like the mini carbide bits used for PCB drilling), high speed, low feed rate, and back-side support. Omit any of these, and suffer.
  9. Violinmaking isn't that much like a race... how do you even quantify "progress"? To me, the biggest problem in documentation is recording exactly what the arching is... not just the height and a few selected templates, but exactly where the convex and concave zones are, what the radii are, inflection points, and all of that. Although I can't present any quantifiable "progress" (other than competition tone awards), I feel that my work got better after I spent a long time studying the arching of good violins in 3-D, either in person or from plate casts. You can document plenty of stuff, but the problem is deciding what matters and finding ways to document that. Since I don't have a good way to document arching, I just try to study at as many good ones as possible, and hope it sticks in my brain.
  10. Higher plate modes = far more complexity and variation = even farther from what happens in the assembled instrument, once the plates are glued to the ribs and soundpost placed. Since the relation between the low modes of the free plate and the low modes of the assembled instrument is pretty poor, if you go higher, it's going to be even worse. Unless you have the same wood properties and same arching, there will be some built-in barriers to duplicating plate modes. Even if you could make that happen, I suspect that the end result would be dissimilar due to damping properties, local variations, or perhaps some of the other dozen or so wood properties that are difficult to measure. This whole idea of matching free-plate modes to some gold standard looks to me like a dead-end with an infinite number of side streets that are also dead-ends. You could spend a long time in there; I'd rather not.
  11. I just got a new bottle of fish glue from StewMac, as my old (~10 years?) bottle was getting low. I use it for random things, mostly, although I do like it for attaching blocks to the form. Easier water cleanup. The smell reminds me of grade school, and those glass bottles with the tapered rubber top. Do they still have those?
  12. I'm sure there are some out there. I'm not one of them.
  13. Similar to a recent thread on liquid hide glue.