scordatura
-
Posts
1142 -
Joined
-
Last visited
Content Type
Profiles
Forums
Blogs
Events
Downloads
Gallery
Articles
Store
Posts posted by scordatura
-
-
Frequently professional orchestras only require the exposition of a concerto so you are safe. Play page 1 of Strauss Don Juan, Schumann Symph. #2 Scherzo for good measure.
-
From the recent instruments that I have seen with cochineal (Joe's varnish?) yield a very intense red color.
-
On 4/4/2019 at 3:00 PM, Don Noon said:
I'm going to say that this mini research project is done now.
In the charts, "C" designates control samples, uncoated but subjected to the same conditions as the others. "P" is the polyester resin, which came to me as the grain sealer, but I used a 5-micron filter to remove the microballoons. "L" is the "I can't believe it's not lacquer", brushable verseion, and V is the vinylester material.
The samples were rectantular Engelmann spruce, coated only on one side, as thin as possible while still getting full wetting. They were put in a lightbox overnight, in the sun for a half day, and then left in the shop to stabilize overnight. I also put some coatings on glass, and then put oil varnish and hide glue on them to test adhesion.
Glass test: oil varnish seemed to stick fine, and (kindof expected) the hide glue could be peeled off. I could scratch the coatings with my fingernail, but the lacquer version seemed to be more resistant. All were water-clear.
Acoustic tests: No surprise that all wood samples were heavier and stiffer with the coatings. I chose to look at the Radiation Ratio (RR) which is a useful stiffness/weight figure of merit. On the longitudinal samples, it's hard to compete with the properties of the wood, so all coatings reduced the RR. The lacquer substitute fared the worst, but also had the heaviest coating... so it's hard to say.
For crossgrain samples (where the wood properties are far less impressive), The vinylester and polyester improved the RR, but the lacquer substitute didn't.
For the damping tests, the lacquer substitute showed significant increase in damping, while the other two polymers were modest (the control samples for longitudinal grain could not be measured, as the sample free-free mode was unclear).
Conclusions: I don't see anything here that would make me really want to try this on a violin, other than the coolness of a liquid coating that stays liquid while working (in the dark, or dim incandescent light) and then having it set up in just a few minutes under UV. The polyester and vinylester might work, but the lacquer substitute looks like it might add dead weight and absorb vibrations more than I'd like... but I do like its flow and working characteristics.
A far better application for any of them would be for coating forms, molds, and tools. You don't have to wait very long for it to cure, like you would with varnish. A caution... all of these coatings give off unpleasant or irritating fumes, especially the polyester.
Edit: one other possible application would be on necks and fingerboards. Let it wet the wood out, then scrub off whatever's on the surface. I might try that.
Now that is a proper research summation!
-
According to the Strad poster, the top is 15 mm and the back 14.5 mm. Yes the f holes are kind of Strad like. When I have played this instrument it has qualities of both a Strad and DG.
-
12 hours ago, Deo Lawson said:
Electric violin with tone issues? Dude. Just change your eq.
I did an analysis of Jean Luc Ponty's frequency output. His eq curve is rolled off starting at the midrange. He is using a Barcus Berry on the recording that I analyzed. No doubt a decent electro acoustic to start. On an instrument like yours you are probably accentuating all of the frequencies (high mids especially) that contribute to bad amplified sound. The amp you use will obviously influence the sound. Acoustic guitar amps work the best.
-
I should have said Addie. Was that who you meant by AD?
-
2 hours ago, catnip said:
I don't have the Strad poster of the Kreisler. I used AD generous illustrator copy of the Keisler in pdf format. I cut it out and tested it against the full scale picture of the back and it matched it very well.
The AD outlines are a bit short. I asked him about this and he said he was going from the cat scans. The ends of the plates are shorter than the Strad poster and Biddulph tracings. That may be a good thing though because the DG lengths barring a couple of instruments are short compared to the modern "standard" length. I have lengthened the long arch on my interpretation. I bought the herdim templates from International Violin which are longer and made symmetrical. Not sure I am convinced about the f hole, neck and other templates though. Making a lot of decisions on the design side. Now if I can execute said designs/concepts...
-
Out of curiosity, what did you use to create your pattern? Strad poster, Biddulf book, etc.? They seem to vary a bit.
-
Very nice. Your antiquing skills are first rate!
-
Very nice catnip. I too am working on a Kreisler copy. The flame of the back looks similar to the original instrument.
-
11 hours ago, nathan slobodkin said:
Those who do not have the skill, understanding and experience to work traditionally have the option of learning how to do so. I suspect it would be easier than becoming a software engineer.
That depends on your background and experience. I worked as a full time programmer for six years and have a degree in computer science. So for me this is another venture down that road. I only wish I had the same experience and training with the traditional methods of violin making. Unfortunately due my current teaching and performing commitments, I cannot pursue an apprenticeship or school at this time.
As far as the other ways if controlling sound, yes there are other aspects. One thing I am reasonably sure of. After a certain point with graduation (thinning), the arching and wood properties take over. Then the set up variables come into play. Bass bar, bridge, strings, sound post, etc.
As a maker working on my #3, currently I am working on trying to carve a scroll that is not “ fubar” (With hand tools I might add!). I would equate it to a young violinist that is learning a Mozart concerto on their own and striving to sound like Perlman in his prime.
-
5 hours ago, JohnCockburn said:
So now we know who's been advising Theresa May!
Strange political times indeed.
-
Hey Don if you sell this fiddle do I get a commission?
-
1 hour ago, Rue said:
So many MN Shar Stars!!!
Yes Jeffery Holmes used to be a partner in crime with Burgess from what I understand. I'm sure it was an interesting work environment.
-
Here is the pamphlet. I think the verbiage is on his website. Sorry pages are last to first...
-
On 3/21/2019 at 5:47 PM, HoGo said:
Most instruments builders use it just to hog out the basic shape of arch and from there it is still looong way to final product. If you had apprentice to do the initial carving using your templates no one would mind...
I think this is what many fail to understand about this process. Besides not everyone has the experience, understanding and skill to do arching correctly. If one does not care about trying their best to control variables, then by all means go by instinct (chance) and live with the results. You might get lucky.
-
This is from the 80s I think at Shar.
-
I was string shopping today and I noticed a very interesting category when I was looking at the filters. It said "Don Noon". I clicked on it and this came up!
-
Does anyone own a touch probe for their CNC? If so what brand, cost, etc.?
-
14 minutes ago, Michael Darnton said:
To my eye, some of the things I'm most interested in are things that software wouldn't do, but that's a limitation of the software and the operator, not the CNC machine.
This is my point. I feel that with the right approach you CAN do what you want. It is all how you execute in the software. This is not rocket science (sorry Don) it is just another skill. For me and possibly others, time is the enemy here. I have so many irons in the fire that I have trouble getting it all done let alone striking while the iron is hot!
-
40 minutes ago, Don Noon said:
the shape is made by dragging a profile around the outline, and ends up with a distinctive shape that I have seen from a number of CNC users. It just screams CNC.
Agreed. I did not like the look of the top of the arch. The contour lines he created were too pinched in the center bout. The way he did the corner areas was also was concerning. In his defense, he said that he was trying to speed up the video. By the look of his videos, he also does other instruments. He may not be that knowledgeable with arching contours on a violin. I am in the process of developing a procedure. I think the way to do the outline and main cross arches is to use a function in Illustrator or Inkscape (freeware I believe) that "vectors" the bitmap. Fusion 360 does not have this vector draw feature. This should be much less tedious and a better outline if done correctly. Starting from a .tiff scan for instance is better than .jpg or .gif.
-
2 hours ago, Don Noon said:
I see this as a typical fault with CNC use... the shape you can conveniently model with the software is not the same shape and experienced maker would be getting by carving.
I am not sure I agree with this Don. If you can recreate the arch from the templates that exist for a given model, your "carving" is your ability to create the curves with the software. Granted there is a lot going on in a curving 3 dimensional space. I have worked quite a bit with Photoshop, Illustrator and a bit of Autocad and feel that it is definitely possible to get good long and cross arching. It will be a bit tedious to execute. It is carving with the software vs. the gouges and planes. The other way would be to carve (with hand tools) the top and back then probe (in high resolution) with the CNC/software.
To me the real question is how to manipulate the arching for a given piece of wood that you are working with. I always remember what Luiz Bellini told me. He said that he was not too worried about thickness. For a given top or back he changed the arching rather than the thickness. This is where experience with understanding the wood and what you want to do with the model and sound come in. If you have a decent model, one could experiment with moving points in the software and go from there. I can say I am on the outside looking in with this problem (amateur).
-
11 minutes ago, carl1961 said:
here is a interesting Fusion 360 video doing the Guarneri 'del gesu' Violin 1741
Carl. This is awesome! It is really cool to see how he approaches the modeling process. Thanks
-
I have a question regarding gouge sharpening. I have read in some books that a very small micro bevel on the in-cannel side (inside) is desirable. It seems that most do not do that. Opinions? It seems as long as the inside is polished, adding another bevel is another variable that is hard to control.
I also see that 15 degrees is mentioned frequently for gouges. I wonder if roughing gouges should be 25 degrees so the edge has more support. Does anyone use a different angle for scroll gouges or the gouge they use to cut the channel on the edge?
Manfio's Bench; My latest instrument...
in Contemporary Maker's Gallery
Posted
Love that curved rasp!