Urban Luthier

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Posts posted by Urban Luthier


  1. As for CG visualization - i think what would be very useful as a study aid is the kind of techniques automotive designers use to study the curvature of class A surfaces. In the old days you'd need tools like Alias to do this but now you can do it in any number of tools like Fusion (Free) or Rhino. 


  2. 1 hour ago, xraymymind said:

    Hey all,

    I wonder whether anyone here has made a Resin/Linseed Oil varnish, to which they did not add any Turpentine (or other solvents) while it cooled (which is something I have always done).

    What was the outcome like? Were you still able to thin it with a solvent to brush later, or keep it thick for glazing purposes etc.?

    Any opinions on this would be much appreciated.

    If you are talking about making a solvent free oil varnish than yes many here have done that. Typically 1:1 ratio of linseed oil to cooked resin by weight. Have a look at the Bass Book by Roger Hargrave. It is all there. 


  3. @David Burgess and @jacobsaunders thank you both. Makes perfect sense.

    One follow up question - for new construction - how much extra wood should one leave on the neck gluing surface to accommodate the tilt? 2-3mm?

    I've seen new cellos that appear to have the pegbox set back a few mm from the neck gluing surface. Like the notch shown where the pegbox meets the neck in @Davide Sora fine drawing. I assumed it was to allow for future repairs. However in light of this discussion,  it makes sense the extra surface is planed at an angle to achieve the tilt as well.

    post-70417-0-81262000-1468622923.jpg


  4. On 6/2/2011 at 6:29 AM, jacobsaunders said:

    Dear Mathew,

    I play the Cello too, since I was 8 years old. During my whole working life as a vm. (with noticeable exceptions) I have been surrounded by colleagues who either don’t play at all, or who could just about scratch out “Ghost Riders in the Sky” if there life depended on it. When an instrument comes in for a re-shoot, one can normally see from the dirt boundary on the fingerboard that the musicians generally play the violin up to ca. 4th. Position on the G String, marginally higher on the D, much higher on the A and almost 7/8ths of the way to the top on the E string. With Celli it is not much different. Therefore the argument about tipping the G String side higher for “ease of playing”, I think, falls completely flat.

    I don’t know any “standard” for Germany, where I lived until 1985 and don’t think there is one.

    To answer you’re question, I would fit a neck, when making a new Cello, or a neck graft on an old one, about 21mm between purfeling and underside of fingerboard on the A side and about a mm less on the C side. On particularly wide or square shouldered Celli, perhaps a little more. As you will know yourself, repairing old ones is normally a matter of “making the best out of a bad job”.

    I'm working on my first cello. The execution aspect of the tilt is still a bit of a mystery for me. @jacobsaunders and others; question for you: To slope down 1mm  from A to C on a cello,  does one plane the neck face on an angle (as pictured in Weisshaar) or does one cut the dovetail joint in the block on an angle to achieve the the desired slant? Would the latter look odd with the scroll/neck turned slightly to the left?

     


  5. 18 hours ago, David Burgess said:

    That's pretty much the way I do it too. But I wouldn't consider the way I do it to automatically exclude other methods. Would you?

    of course not - the way that is shown in the post above by @Geigenbauer [where did post numbers go?!!] looks practical with the added benefit of being able to cut many blocks at once (in my case enough to last decades). In the end this is a far more practical workflow

    18 hours ago, David Burgess said:

    When I was doing volunteer work on a "Habitat For Humanity" home-building project or two, miter saws were about the best thing we had going, whether for rough framing or picky finish work. I was not a professional home builder, so I tried to learn from those who were, who brought their miter saws. The bottom line is that I don't consider a miter saw to be nearly as dangerous as some other types of saws. I've used various sorts of saws quite a bit (including chain saws and circular saws) for decades, and 'the only saw which has drawn my blood so far has been a hand-powered saw.

    regarding danger of a miter saw- i would agree. It is the table-saw that scares me. I have a miter saw and have used it extensively for home renos (trim work and mouldings). Easy stuff compared to builders who do roof framing -  all those angles and so many ways to mess up unless one knows what they are doing.


  6. Since I've never been able to get the block cutouts on my moulds perfectly square, I don't bother using power-tools to cut the corner blocks. I simply cut them to length by hand using a bench hook appliance and carcass saw (couple of mm over), glue them to the form and level them with a block plane (test for rocking on a sheet of glass)


  7. On 9/5/2020 at 12:34 PM, J.DiLisio said:

    I’m just putting the finishing touches on the baroque del Gesu model.  The loudness and depth of the full thickness plates is really eye opening. There was a bit of adjustment in the white to open it up, mostly around the channel and c bout ribs but the back is about 6.8mm and the top around 3.5 at the thickest points.

    I just put in a small amount of scoop to the fingerboard and that made a significant difference in feel.  The last thing that needs attention is the saddle that I had based on the Chardon del Gesu. I realized that the sides should have a wedge shape to keep it from sliding down with the pressure of the tailgut.  

    I’ll post more photos once it’s all polished up.

    CB177795-563E-47BE-AB42-48FC017F8513.thumb.jpeg.dae8525d85342796af226ac0ff3dbec1.jpeg

    nice work - love the setup


  8. 14 hours ago, David Burgess said:

    I think Hargrave once posted here that he thought original baroque neck projections (fingerboard height measured at the bridge) were about the same as modern necks today, and I have no reason to disagree.

    Roger argues the same for the rest of baroque setup in his articles published in the Strad a few years back. I haven't read the current Strad letter exchange, but if it is about  saddle hight - the argument is the same. Quote from Roger's original article

    "BAROQUE TAILPIECES varied considerably, from flat inlaid maple to slightly arched solid ebony. However, in most cases the tail gut passed over a bottom nut or saddle that was initially no higher than the belly edge. The gut entered the tailpiece from below, effectively lifting the tailpiece to the height of the modern saddle. Making and mounting a Baroque tailpiece in this way creates a string angle at the bridge that is entirely similar to the modern angle.'"