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Michael Richwine

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Everything posted by Michael Richwine

  1. It looks like a "made to look old" from around the late 19th - early 20th Century. I don't know whether that sort of thing was marketed in Europe or Britain, but violins like that are by no means rare in the USA. Just the kind of thing an enterprising Yankee merchant would come up with. First one I ever saw was in Mr. Atchley's shop, and I've seen a few since. They look convincingly old in many ways, but are just too new, with too little oxidation or playing wear, and obviously fake labels.
  2. Good to know, thanks! My ignorance of bows is doing its best to remain undiminished, but time and a willingness to ask naive questions is making inroads.
  3. The slide looks like abalone, but the frog is only half mounted, so wouldn't that relegate it to " fairly late German student bow"?
  4. That's why I qualified what I wrote to "flat surfaces". Not having lived back then, or worked with them, I don't know the practical differences among sharkskin, horsetail, etc. I do know that pumice and a little oil and a rag wrapped on a block work pretty well for the tasks you mention. When I first started working wood for money in the 1950s, the only choices readily available were flint paper, garnet paper, and emery cloth; and protein glue, probably bookbinder's glue, was still presumably the primary binder for sandpaper, still all pre-WWII technology. We didn't really see Elmer's Glue-all until around 1960, although it was introduced in 1951. Casein glue was easy to buy in the local hardware store. I use curved scrapers to pretty good effect, but rubbing surfaces like fingerboards out still looks better. These days I just use paraffin oil and wet-dry sandpaper, but I can try burlap & pumice on a block and see how it works.
  5. I've been using a half-pint canning jar on a trivet inside a small sauce pan on a reliable hot plate since the 1990s. It's kinda clunky, but has always worked well. Since I'm remodeling the shop, maybe it's time to free up some bench space and try one of those bottle warmers. I'm one of those who is reluctant to abandon something that already works well, but I really could use the extra space, and that old pan is awfully crusty.
  6. Pulverized flint or garnet, strong paper, and bookbinder's glue (hide glue with vinegar and glycerin). No doubt available, just not terribly practical nor economical. Would have been pretty expensive, and, then as now, you get a better surface, faster, on flat surfaces, from scraping. Sanding only started making sense when sandpaper became really inexpensive to use. I still think it has more limited application than most.
  7. FWIW, all I'm interested in right now is getting a scanned point cloud that my colleague can use in a professional cad/cam application. I don't have any current interest in 3D printing. So far, I've spent about $120 on a used 6gb graphics card that is compatible with the free software that I will download as soon as the card comes in. Since I do a fair amount of photo and video editing, the GPU upgrade will be a nice side benefit over the 1gb unit I have currently.
  8. Dunno. Don't know whether it was even right or not. Seemed to go awfully low. I wasn't bidding, so just a spectator.
  9. Just thought I'd raise a flag. I'm not bidding on this one, but it closes today, and it's only at $1800 ATM, with some experienced bidders involved. https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2047675.m570.l1313&_nkw=darnton+violin&_sacat=0
  10. Working with a large industrial production CNC router. Not sure of its exact specs, but it has at least a 4' x 8' bed and has a 4th axis setup. The guy I'm working with, who owns the machines, says all he needs is a point cloud file. I'll work with him from there, and learn as I go. I started with machine code in the 1960s, and then Fortran and Cobol on IBM 360s and many generations up to now, but there are plenty of gaps in my experience that need to be filled in. I need a CUDA compatible card to use Metashape, so it's a done deal as far as I can tell, always with gratitude for the caveats.
  11. I've watched a tutorial on Metashape and Blender. It seems I need a GPU compatible with CUDA, which I am in the process of acquiring. This seems relatively straightforward and does produce a point cloud that I can use to produce CNC programs necessary to machine duplicate plates, as best I can tell. There are other projects where the capability to scan shapes would be very useful.
  12. I'll get a 6gb graphics card (GTX1060) that's compatible with the photogrammetry software for around US $100, and should be able to do some preliminary attempts in a few days or maybe a week, depending on how my brain and other workload/ customers treat me. There are some good tutorials on YouTube. I'll post some short updates as things go along.
  13. The results will probably be ambiguous, but at least I'll learn something and gain a new skill. Never a waste of time.
  14. That looks really interesting! I'd have to get a different GPU for the open source software and CUDA, but the current demand for gamer cards seems to have driven the cost of used GPUs way down, even for 4 gb plus .
  15. It's pretty rare to get three players to agree so thoroughly, especially with such close competition, because I had selected each of those instruments with them specifically in mind. The fact that they ranked them in the same order was certainly worth exploring, so I'm interested in investigating those specific instruments. Education is expensive. As it turns out, Jerry Lynn's suggestion of looking at photogrammetry is pretty interesting. Looks like I may be able to achieve my goals with only a camera, my existing photo setup, and some open source software. There's time involved in learning the software and coming up with files that can be used on the CNC, but today it got a whole lot easier. How do you learn stuff without trying it out? If you have a hypothesis, test it! I watched my former boss test different ground formulations on identical (as near as possible) violins for six years, comparing one formula against the other. I would never have believed a ground makes so much difference if I hadn't seen the development process myself. So I'm willing to invest the time and money it takes to test out my hypothesis and see whether it works or not. I can keep the wood the same, cut from the same logs, aged the same, and shaped with considerable precision. To do it with CNC makes it possible to investigate different shapes with control, using a minimum investment of time and materials. I'm sure other makers have done this sort of thing, investigating other variables, but I haven't read about it.
  16. I think that the Creality scanners can do the job I need, but I don't yet know whether they can give me a plain IGS file that I can use with a CND router, so I have more to learn. I'll look in to photogrammetry as well. I have a good camera and graphics card. I'm a little shy of Autodesk products, though. They're not exactly aimed at us one-horse operations.
  17. Definitely on the right track now. Seems I can get what I need for around us$750. Several competing brands and models at that price point that will handle violins and mandolins. Need to learn more and read more reviews and specs, but resolution of .01mm seems plenty. and volume of 500 x 1000mm also seems adequate, even for possibly more ambitious projects.
  18. Thanks, that's a step in the right direction! I've seen the results from some of the rinky-dink ones, so there's definitely a minimum acceptable standard.
  19. I've initiated contact with a couple of local firms, but no response yet. Maybe too small a job to be interesting. Owning my own scanner, I have better control over time and other factors. I will continue to explore all avenues until I come up with an acceptable solution. Probably should have done this a few years ago.
  20. A few months ago, I took 15 fiddles down to a music town to be evaluated by three of my favorite clients, full-time performers who are friends and generous with their time. These ranged from inexpensive Chinese to pretty expensive German Kunstgeigenbauer instruments, all selected because I thought they might be interesting to these players, and I wanted some feedback to help me serve my market better. To my surprise, all these players ranked the instruments nearly identically in order of preference. Price seemed to have little relationship to how they were ranked. I got to looking at them carefully, and the most preferred instruments all seem to have very similar arching. I'd like to run some experiments, duplicating the arching on the most successful examples that were tested, then assembling those plates to existing ribsets that I have available, and having a listen at how they compare. I have access to inexpensive instruments damaged in transit, from which I can scrounge virtually identical ribsets, plus some decent tonewood sets for plates which should work. I also have access to an industrial CNC router that is already set up for violin parts. The only problem is that the router was always been programmed manually to a specific original design. I need to come up with a scan of the shapes I want to duplicate and test. I've contacted some scanning services, but am not getting anywhere very fast, yet. I've seen some inexpensive 3D scanners, but am not impressed by anything I have seen yet. If I had my own scanner, it might pay off on this project, and also on some other future projects. All production oriented. Does anyone have a recommendation for an affordable scanner capable of 3D scanning violin plates and producing a point cloud in an IGS file format?
  21. I ran about 75,000 board feet (a railroad flat car load) of pine a week through my little shop each week for years, turning it into furniture. Also did custom finishing and finish design for some years after. There are indeed a lot of different approaches, depending on a persons goals for final outcome, skill level, equipment, etc. That's why I recommended Flexner's book, because, like Courtnall and Johnson's book regarding violins, it's a good primer on wood finishing in general and won't lead a person far astray.
  22. Buy Bob Flexner's book Understanding Wood Finishing. It won't tell you everything there is to know, but it's only one book, and it's a good start. More importantly, I never found much in it to argue with.
  23. I just don't buy from pictures unless it's an absolute, screaming bargain, and even then I still win some, lose some. I'm experienced enough as a photographer to know what lighting can hide.
  24. They claim 97 CRI for "Full Sun" 2700K, but they also offer other soft white 2700K bulbs that are not the GE "Full Sun" brand. They are not too bright for me in a work lamp; I can just move it a bit farther away. Inverse square law applies. Double the distance should give one f-stop lower, equivalent of half the lumens, unless I've got my physics wrong. I use high output LED 4 foot fluorescent replacements, @ 4000 + lumens 80 cri for general shop lighting, and keep the high CRI bulbs for task lighting at my bench.
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