Michael_Molnar

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About Michael_Molnar

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    Stargazer
  • Birthday 09/15/1945

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    http://www.michaelmolnar.com
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    Michael R. Molnar

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  • Gender
    Male
  • Location
    Warren, NJ
  • Interests
    Astronomy, History, Optics, Great Ideas, and Interesting People.

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  1. This is a lovely cabinet. I suggest adding air vents, (fan), thermometer, and hygrometer (for relative humidity readings) as David recommended.
  2. It's not fused amber but an amber colored colophony similar to dark FF rosin. It is brittle enforce cooking according to Kremer. I have no experience with it.
  3. Mercury is a toxic hazard once it is out of the lamp. It is the UV source when ionized in a vapor such as in fluorescent lamps. So, I dispose of my old lamps at the recycling center.
  4. Beware of cataracts developing in your eyes.
  5. Edgework is arguably the most important part of great craftsmanship.
  6. You need to send your Uncle Louie to pay a visit to your friend.
  7. The amount of scraped material depends upon the surface quality and how close you are to the final shape. I like to leave some meat on the bones as it were. My CNC'ed plates are about 5mm thick overall. I then scrape the top to a final smoothed contour. Then, I remove the excess as I graduate the interior. A lot of handwork remains after CNC'ing.
  8. Now here is a photo of hogging out the inside of the plate. Note how the f-hole cutouts fall out. You can also see how I use the bottom tab and tie-downs to raise and support the upside-down plate. After I cut off the tabs and tie-downs, I will start purfling. Life is good when everything works.
  9. This is close to my experience and gut reasoning. I feel that the soundpost issue is also one of transmission, namely a good solid contact between the post ends and the plates. I get better results when I dampen (lick) the post's ends as I shave them down. I make a tight fit compressing the damp fibrous ends. This ensures good contact improving transmission of vibrations. Well, that's my two-cents worth.
  10. The plate shape for a top is identical to a back. I use the same program for both. The neck button will be removed as well as the bottom tab from a top. There are three reasons I attach these tabs. 1. The tabs reduce breaking the glue seam due to router vibrations. This is insurance in a way. 2. I use these tabs for holding down and supporting the plate upside down to hog out the inside. 3. The bottom tab serves as a narrow extension for the end mill to start cutting the wedge end gently. Without it, the end mill does not know where the edge begins. My plate wedges are various lengths. The tabs cut the wedge down to size and avoid crashes. Of course, the button is not cut off a back plate. I committed that sin only once amd have been doing penance ever since.
  11. I am back on the air with the CNC. I laid out an entire new top trying to get closer to a Strad contour. I had to redo the f-holes. My program lets me tweak the position X,Y position and rotate them a few degrees around the vertical Z axis at the CNC machine. That f-hole "needle" end mill is only 0.75 x 6 mm going at 35K RPM. I go down to 5 mm in three passes at a snail's pace. Although this is a test plate of red spruce, 0.41 density, I may use it because it came out so good. I guess I am getting good at this. Usually I destroy one or two plates before getting a good one. If you look closely you can see a surface ripple that I blame on a cheap ball socket screw assembly on the Y-axis. However, I am not after a micron finish. This plate will easily clean up with a scraper. I am pleased with so little tear out. This contour cutter is a bull-nosed (not a ball end) 1/4" end mill from Precise Bits (0.06"radius corners 2 flutes. I immediately noticed from its cutting sound that it is s good cutter. Tomorrow, I will flip this plate over and hog out the inside. The f-hole center plugs will then fall out. I also expect to get in some brown oxide pigments for testing. I can never get enough pigments.
  12. Right. It's a lousy bow no matter.
  13. Great photos of the Alard. Lovely varnish colors. Nice workmanship on yours.
  14. Also, check the blade sharpness. Router bits will also become dull and even wear down to smaller diameters! Yes, tungsten carbide does wear like any tool steel. I now avoid hammering the purfling into the groove because this can peel over the black edge as the purfling softens when wet with glue. Dry fitting is good practice. I highly recommend #10A surgical blades for cutting bee stings. They are thin, pointy, and sharp.