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About chungviolins

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  • Birthday 01/17/55

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  1. Integral bassbars

    I don't think you will. Try the experiment the other way around, gluing the bass bar only in the center, and see what happens. ---> I didn't clarify, what I meant was if you don't put any gap at all.
  2. 19th c. Czech Violin Gouges for sale

    Do you have Stubai or Dastra complete scroll gouge set? Pls PM me. Thanks,
  3. Veritas block plane

    DGSR, thank you for the link. I'm looking for the Veritas block plane to modify the mechanism. Veritas block plane is well made but blade mechanism is of bad design. There are two different pitched screw in the mechanism. I think it will improve the mechanism by reversing the handness of one screw part. Any mechanism of direct linear movement is not good, it's very hard to adjust small amount, usually you have to move back and forth until you get it right. Lee Nielsen mechanism is no better, basically same design as Veritas. Record block plane (now defunct) has a better adjustment mechanism, it utilize a lever system making possible for fine adjustment. This lever reduces the movement of the blade 1/4 of the screw movement, but still lot of plays. You have to move the screw more than once to set it up correctly. I've been using my own modification of the Record plane, I use the teeth mechanism but not using the screw. I can adjust by hitting the blade with a small brass hammer for advancing and retracting, it virtually eliminates any play and adjusting takes mere seconds. Koo Young
  4. Integral bassbars

    with the side affect of causing more bass bar distortion in the upper and lower bouts, which are weaker (since they are trending toward "end grain") ---> You are correct, that's why we have to fit very well with tension distributed evenly along the BB, that is BB rolling evenly and fast, when you're doing tensioned BB. Tension or bending is more concentrated in the middle area where it is thicker than upper or lower bout area, in the both ends of the BB where is more gap than in the middle, there are supposed to little less tension: it just moves more when you are fitting it. And you're not supposed put too much tension any way. What do you think has been accomplished by shifting the distortion to a different place? Have you really thought this through thoroughly? ---> As I said in the OP , we fit BB in a slightly deformed curve so that it is better fit and much less tension in the BB itself when it's strung up than that of a top w/o tension: suppose if you fit BB without tension and glued only at the end point (this is just a Gedanken experiment), when this violin is strung up you might see a gap in the middle because of the bending of top due to string tension. I've been thinking this thoroughly for many years now, I'm convinced this is the actual reasoning behind the BB; But it's possible that whoever came up with a tension BB long time ago, he might not have realized the reasoning I described in the OP. K Y Chung
  5. Integral bassbars

    I'm sorry that it took me a while. Bass bar is one of the things which is not fully understood, when we teach/learn violin making , emphasis is usually on "how to" not "why". (Another being the neck angle/ string angle on the bridge but that's another topic for another time.) When we string up a violin, a few small changes happen on the violin. (These changes are very small, but unless it's addressed it'll get amplified over the time.) 1. Finger board goes down. (Please see the attached diagram. Black lines before strung up, red lines after) 2. Upper and lower portion of the arches bulges out (goes up) and middle portion of the arch is goes down a bit (at the bridge). 3. Upper block and lower block area buckles slightly inward. 4. Back plate bends very slightly but it's much lesser degree than top plate so I didn't indicate. Without BB, the changes I described above is so great that violin (top and FB) wouldn't be stable. So the main reason (#1) for installing BB is that it counter-balances the force of the strings, and make the violin shape more stable. Other reasons are, #2 : BB supports the bridge foot area on the bass side (Treble side; sound post). #3 : BB connects the upper bout and lower bout, reinforces the breathing mode of the violin. #4 : Incidentally BB raises the tap tones of the plate so that we can make the top thinner but this is not the reason we install BB. From above, now we know why we put gaps when fitting BB. With full string tension, top bends upwards, so when we press down the both ends when we fitting BB, we simulate the change of the top shape which will occur when the violin is strung up. But we have to remember that this gap and tension of it will dissipates in time no matter how big gap you put it. (After BB is shaped after glueing the tension becomes much smaller than you felt when you were fitting, and as the wood dries and the whole violin settles the tension will eventually be nonexistent, so argument of whether we put gaps or how much becomes a moot point after many years.) Koo Young Chung
  6. Integral bassbars

    I don't know what you had thought unless you tell me.
  7. Integral bassbars

    OK, I'll explain it in a couple of days, but I want you (plural) to think of yourself. (Please post your idea here if you want.) The real reason is very simple but not understood correctly by many makers. To understand why we put gaps, you should understand why we put the bass bar in the first place. Of course these two are closely related. Thanks, Koo Young
  8. Integral bassbars

    The answer lies in why we put gaps at the ends when we fit the bass bar. I agree all other explanations, but the real reason we do it separately is that we can adjust the amount gap,i.e., amount of tension. If you don't understand why we put tension between the top and bass bar, all other argument are moot. Koo Young Chung
  9. Veritas block plane

    Hello I'm looking for a used Veritas block plane (9 1/2 size) in good condition and good price. Or possible trade with several Record planes, I have Record planes in excellent condition. If you have one, please PM me. Thank you. Koo Young Chung
  10. Utility Knife (Hard)

    Hello My friend Steve Erbe makes knives for violin makers. I highly recommend his knives (I use them.) If interested, please PM me. Or contact him directly ----> Koo Young Chung Chicago,IL PS : Steve is a member here, but he cannot start a topic yet.
  11. Looking for scroll gouge set

    If you have a scroll gouge set for sale, please PM me. Thank you. Koo Young Chung
  12. Recognize this label?

    I've seen this label before, but I cannot htink of the maker/company. Anyone recognize this label? Another label is pasted on top of this so only the top part is visible. Photo is not great. Thank you. Koo Young
  13. VSA

    Thanks, I can open the website but cannot login now. Anyone have the same problem or it' just me?
  14. VSA

    Is VSA website working? KY
  15. Chalk Fitting

    I use Staedtler eraser. Koo Young