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ezh

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  1. Sigh ... the web site is different now, so all those references are bad. The pictures I was referring to are in https://www.dgviolins.com/number-18 But I'm now doing some stuff with understring fine-tuners that I really like. See https://www.dgviolins.com/fine-tuners And all my HF stuff is at https://www.dgviolins.com/hardanger-fiddles Dave Golber
  2. "https://www.dgviolins.com/hardanger-fiddles" New web site. Correct is https://www.dgviolins.com/hardanger-fiddles
  3. Take a look at https://www.dgviolins.com/fine-tuners . (The whole web site section on Hardanger fiddles is https://www.dgviolins.com/hardanger-fiddles) I've started putting my should-be-patented finer tuners for understrings as well as playing strings on the tailpiece. I think they are great! Dave Golber
  4. When I see an old fiddle with plain pegs, or completely missing pegs, I say "Oh, good. I can just put in new pegs". With old decorated pegs, I can put new ebony shafts on the old decorated heads. But it's a big deal. Dave Golber
  5. A famous quote "No wonder you are having so much trouble tuning. The holes are square and the pegs are triangular!" Yes, 1/100 of a turn is possible ... but that changes the pitch by about 50 cents! The pegs I put in fit.
  6. 1 is correct. 2 and 3 is not correct. The diameter does indeed have a little influence, as does the diemater of the tuning peg. I have tested reducing the diamter of the pegs for the undertstrings in the pegbox, which works fine, but is problematic when the pegs or holes need to be shaved off a bit over time. Witther gerared pegs are tiredsome to use as are pegs with less diameter. The highest tuned pitced understring is more difficult to tune than the lower, in my experience. My calculations certainly do not take many fine points into account. But the first one found 50 cents rise, when I measured about 40 cents. I think that's a great validation ... especially when the measured 40 cents wandered up to 50 cents. I'm not surprised that there is "a little effect" from the diameter of the string. The diameter of the peg of course has a strong effect. If the peg has half the diameter, then the same turn of the peg tightens the strings by half as much. The method of the calculations is verified by the first measurement. So I tend to believe the other results.
  7. "Find those hooks"? You mean getting the string on the hook? Yes, it's harder than for the usual set up. But not impossible. Given that players don't change their understrings very often (they probably change wives or husbands more often than understrings), I figure the extra difficulty is worth it. Here's the analysis of "impossible to tune an understring with ordinary pegs". More mathematics than usually here in Maestronet ... but you can read it ... The question is: why fine tuners for steel strings and not gut strings? I reason: When you turn the peg on gut string, some of the turning stretches the string, and some of the turning increases the tension. With a steel string, the string doesn't stretch much at all, so most of the turning goes into increased tension. The calculations below show this is true. The calculations show that 1. For the same turn of the peg (or fine tuner), change in pitch (in cents) is much higher for steel than gut. 2. Diameter of the string does not change this. 3. The difficulty of tuning is higher for a lower pitched string. The reason for the strange numbers (F#; 298mm string length, etc): I work mostly on Hardanger fiddles these days, and these are typical numbers for those instruments. The calculations were done in Mathematica. What is below is cleaned up from the Mathematic forms. Young's modulus of gut = 0.15 * 10^9 from "Mechanical Comparison of 10 Suture Materials ...", Greenwald et al, Journal of Surgical Research 56, 372-377 (1994) Density of gut = 1.276 from https://www.cs.helsinki.fi/u/wikla/mus/Calcs/wwwscalc.html. I use 1.3 (* EJH Hardanger "E", tuned to F# 0.215mm diameter Tuner to bridge 42mm Bridge to nut 298mm nut to peg 33 mm ------------------ Total stretched length 373mm. Fine Tuner: Long arm 21mm short arm 9mm Ratio: 0.43 Thread of screw is 2mx0.4 So full turn of screw advances screw by 0.4mm So full turn of screw stretches string by 0.4x0.43 = 0.17mm Of course a fine tuner is capable of much finer adjustment than a full turn of the screw If diameter of peg at the string is 6mm, then 1/100 turn of the peg is 6 Pi/100 = 0.19mm ... about the same. So this 0.17mm is in the neighborhood of the finest possible adjustment of a peg. ------ Actual measurement: Full turn of screw raised pitch 35 to 45 cents *) (* Steel string, Diameter .215mm, vibrating length 298mm. Total length 373mm. Tuned to F# *) (* What happens to pitch if we stretch the whole string by 0.17mm ? *) afreq=440.;semitone = 2.^(1/12); fsharpfreq=afreq*semitone ^9 = 739.989 (* f=Sqrt[t/(m/l)]/(2*l); t= tension Newtons; m= mass of string Kg; l = length meters *) (* Solve for t: t= 4mlf^2 *) diam = 0.215; (* mm *) areamm2= (Pi/4)*diam ^2;(*mm^2*) volmm3 =areamm2*298; (* mm^3 *) volcc=volmm3/1000; massgm=volcc*8.; (* Density of steel about 8 *) masskg=massgm/1000 ;(* kg *) t0=4*masskg*.298*fsharpfreq^2 = 56.4937 (* Starting tension in Newtons *) (* t/area = stress; deltalength/length = strain; stress = ym* strain; ym in Newtons/square meter*) (* So New t = old t + ym*area*(deltalength/length) *) ymSteel = 200.*10^9; (* Youngs modulus *) aream2=areamm2/10^6 (* The tension goes up *) t1=t0+ymSteel*(0.17/373)*aream2 = 59.803 (* So the new frequency is *) f1= Sqrt[t1/(masskg/.298)](1/(2*.298)) =761.354 Log[2,f1/fsharpfreq]*1200 = 49.2768 (* Change in frequency in cents *) (* Measured was 40 cents. So this is pretty good! *) (* ************************** *) (* Allow for stretching 373 mm stretches 0.17 mm. So vibrating mass goes down by *) factor = 373./(373+0.17) = 0.999544 (* So freq is *) f1star=Sqrt[t1/(masskg*factor/.298)](1/(2*.298)) = 761.528 Log[2,f1star/fsharpfreq]*1200 = 49.6713 (* Change in frequency in cents *) (* differs only by half a cent from calculation without stretch factor *) (*********************************************************************************) (* Conclusion: pitch goes up by about 50 cents. *) (* And this is with about 1/100 turn of the peg! *) (* So this is clearly why we need a fine tuner on a steel string *) (* This is also a full turn of the fine tuner screw. Pretty clear that fine tuner can get within one cent *) (******************************************************************************) (* What happens if we change the diameter but keep everything else the same? *) diam = 0.430; (* mm *) (* Double the diameter *) areamm2= (Pi/4)*diam ^2;(*mm^2*) volmm3 =areamm2*298; (* mm^3 *) volcc=volmm3/1000; massgm=volcc*8.; (* Density of steel *) masskg=massgm/1000 ;(* kg *) t0=4*masskg*.298*fsharpfreq^2 = 225.975 (* Starting tension in Newtons *) (* t/area = stress; deltalength/length = strain; stress = ym* strain ym in Newtons/square meter*) (* So New t = old t + ym*area*(deltalength/length *) ymSteel = 200.*10^9; (* Youngs modulus *) aream2=areamm2/10^6 (* The tension goes up *) t1=t0+ymSteel*(0.17/373)*aream2 = 239.212 (* So the new frequency is *) f1= Sqrt[t1/(masskg/.298)](1/(2*.298)) = 761.354 Log[2,f1/fsharpfreq]*1200 = 49.2768 (* Change in frequency in cents *) (* ************************** *) (* Allow for stretching *) (* 373 mm stretches 0.17 mm *) (* So vibrating mass goes down by *) factor = 373./(373+0.17) = 0.999544 (* So freq is *) f1star=Sqrt[t1/(masskg*factor/.298)](1/(2*.298)) = 761.528 Log[2,f1star/fsharpfreq]*1200 = 49.6713 (* Change in frequency in cents *) (* differs only by half a cent from calculation without stretch factor *) (*******************************************************************************) (* These are the same change-in-frequency numbers as for the smaller diameter. So diameter doesn't matter. *) (*******************************************************************************) (* Let's look at gut for the same parameters *) (* Density is 1.3 , Young's modulus is 0.15*10^9 *) diam = 0.430; (* mm *) areamm2= (Pi/4)*diam ^2;(*mm^2*) volmm3 =areamm2*298; (* mm^3 *) volcc=volmm3/1000; massgm=volcc*1.3; (* Density of gut *) masskg=massgm/1000 ;(* kg *) t0=4*masskg*.298*fsharpfreq^2 = 36.7209 (* Starting tension in Newtons *) (* t/area = stress; deltalength/length = strain; stress = ym* strain, ym in Newtons/square meter*) (* So New t = old t + ym*area*(deltalength/length) *) ymGut = 0.15*10^9; (* Youngs modulus *) aream2=areamm2/10^6 (* The tension goes up *) t1=t0+ymGut*(0.17/373)*aream2 = 36.7308 (* So the new frequency is *) f1= Sqrt[t1/(masskg/.298)](1/(2*.298)) = 740.089 Log[2,f1/fsharpfreq]*1200 = 0.233998 (* Change in frequency in cents *) (* Allow for stretching *) (* 373 mm stretches 0.17 mm *) (* So vibrating mass goes down by *) factor = 373./(373+0.17) = 0.999544 (* So new freq is *) f1star=Sqrt[t1/(masskg*factor/.298)](1/(2*.298)) = 740.258 Log[2,f1star/fsharpfreq]*1200 = 0.628425 (* Change in frequency in cents *) (**********************************************************************************) (*So the same peg or fine tuner manipulation that raises the pitch of a steel string by about 50 cents raises the pitch of a gut string about 1/2 of one cent *) (**********************************************************************************) (*********************) (* See if pitch makes a difference *) (* Highest Hardanger understring is at B. It is steel. *) (* Actually nut to peg is longer, but here will use the same number *) semitone = 2.^(1/12); bfreq=afreq*semitone ^2 (* f=Sqrt[t/(m/l)]/(2*l); t= tension Newtons; m= mass of string Kg; l = length in meters*) (* Solve for t: t= 4mlf^2 *) diam = 0.215; (* mm *) (* Actually 0.22mm for usual string. But keep same number as "E" string *) areamm2= (Pi/4)*diam ^2;(*mm^2*) volmm3 =areamm2*298; (* mm^3 *) volcc=volmm3/1000; massgm=volcc*8.; (* Density of steel *) masskg=massgm/1000 ;(* kg *) t0=4*masskg*.298*bfreq^2 = 25.1651 (* Starting tension in Newtons *) (* t/area = stress; deltalength/length = strain; stress = ym* strain; ym in Newtons/square meter*) (* So New t = old t + ym*area*(deltalength/length) *) ymSteel = 200.*10^9; (* Youngs modulus *) aream2=areamm2/10^6 (* The tension goes up by the same number of Newtons as for the "E" string*) t1=t0+ymSteel*(0.17/373)*aream2 = 28.4744 (* So the new frequency is *) f1= Sqrt[t1/(masskg/.298)](1/(2*.298)) = 525.354 Log[2,f1/bfreq]*1200 = 106.945 (* ************************** *) (* Allow for stretching *) (* 373 mm stretches 0.17 mm, So vibrating mass goes down by *) factor = 373./(373+0.17) (* So freq is *) f1star=Sqrt[t1/(masskg*factor/.298)](1/(2*.298)) = 525.474 Log[2,f1star/bfreq]*1200 = 107.339 (* Change in frequency in cents *) (* Allowing for stretching differs only by about half a cent *) (**************************************************************************) (* So, for a steel string, the same peg or fine tuner manipulation that raises the pitch from F# by about 50 cents raises the pitch from B more than 100 cents. *) (**************************************************************************)
  8. What's the wood? I made a couple with hard maple for the nacks, since i was worried about carving a HF head in curly wood. I had a complaint that the neck was too heavy. Now I'm using soft (curly) maple, which saves a lot of weight. You can get away without the cheeks by having the walls bulge _in_ at the G string, so the G string can run up against the wall without bending over the top edge of the peg box on the way to the nut. Similar at the E string. Not sure this saves much weight. Do away with the scroll? (Gasp!)
  9. Oh ... about the understrings sharing two hooks among the five understrings: I did a little bit of repair work on a Harald Lund fiddle. He set five separated hooks into the front edge of the streng haldar. Probably glued into holes. There's a picture in https://www.dgviolins.com/lund-repair I did a bit of experiment: I glued (epoxy) a hook into a piece of wood and hung a 10 kg weight from it. In two week, no sign of movement. Dave Golber
  10. Coming very late into this conversation: I (usually) use geared pegs for the understrings, and regular ebony pegs for the upper strings. So you can pull the upper string pegs out sidewise when changing a string. Instead of the Wittner geared pegs, try the "Perfection Pegs". Before you cut the ends _outside_ the peg box to length, put them on a lathe, grabbing the small end. Turn the part _inside_ the peg box so it's all uniform diameter. Otherwise the understring may sit partly on the big diameter and partly on the small diameter. The Perfection pegs don't have as fine a ratio as the Wittners, but this is partly compensated by the small diameter. I did some calculations, and saw that (to be emphatic) it's impossible to tune a steel string correctly without a fine tuner. And extremely impossible ( ) to tune a low tension steel string without a fine tuner. I think fine tuners in the streng haldar is the way to go. Here's an early version: http://dgviolins.com/images/Bridge4.jpg Dave Golber
  11. Looks like my (old) Gewa (was that who made it?) iron. Came with brass part _very_ unpolished. I had to do a lot of work to polish it.
  12. Gracious! i see that I am coming into this conversation years late. But several things I want to say: Yes, Sverre Sandvik's book is not a good way to learn fiddle making. And Eldon Ellingson's translation is pretty bad. What I recommend is to learn to make a violin - there are lots of good books around and maybe even knowledgeable people to help. Then go look at some good Hardanger fiddles, and make measurements. (In the US, you can go to the annual meeting of the HFAA.) I always thought that the usual head of a HF was the lion from the Norwegian coat of arms. (Amusement: Sandvik never says lion, dragon, or anything ... he just says "head".) You can see my stuff at www.dgviolins.com Dave Golber
  13. I've made and worked on lots of HFs. Yes, you need an "understring guide" in the pegbox so the understrings don't rest on the upper-string pegs. I prefer to fit a slip of bone above the A-peg. I don't like to drill a hole through the side of the peg box ... after all, in a violin shop, this would be considered defacing the instrument and get you fired. On my own most recent instruments, I am using "Perfection Pegs" (aka Pegheds aka Knilling Pegs) for the understrings, and regular pegs for the bowed strings. I think the understrings - which are unwound steel - need fine tuners for the same reason that a violin E needs a fine tuner. Players love them. I did Perfection Pegs for the playing strings on one instrument. But when a string breaks, you need to pull the peg out until the string hole is in the right place, in order to put in the new string. But you can't pull the Perfection Pegs out ... they screw into the wood. So I'm using ordinary ebony pegs for the playing strings (with decorated heads, of course.) Perfection Pegs: You can get them with ebony heads. There is a metal piece that runs up several mm into the head, so you can't cut them too short. I guess you can transfer the decoration from an old peg to the Perfection Pegs. Depends on size, etc. I'd do it myself, and not get Chuck Herrin involved. Here's my own stuff: http://www.dgviolins.com/newHFs.html Dave Golber
  14. I assume you looked carefully for writing inside ... with a light? The violinistic scroll ... Vestland guys were doing this mid 1800s - Anders Heldahl. Doesn't look too old to me. And is that inlaid purfling? And it's worth pointing out: the decorations on the two halves of the fingerboard are completely different. I think it's very likely that one is a replacement. Probably the upper (near the nut) half. That's where the wear takes place. (Of course, one can prevent this wear by not playing the instrument ) Here's my stuff: https://www.dgviolins.com/hardanger-fiddles Dave Golber
  15. I'm working on a very ordinary school violin. It has Kaspari pegs. Composition bushing glued into head-side of hole. The two ends of the peg tighten down on the bushing when you tighten the screw. Three of the four pegs work fine ... they ooze around nicely. The fourth chatters - that's the best I can describe it. Tried lots of things - opened it up, smeared on peg dope, added mylar washers, etc, etc. No change. Any suggestions? Taking it out? Hah! The holes are 9 mm! Not a fiddle worth the labor/money of bushing the holes or hole ... Dave Golber
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