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David Beard

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Posts posted by David Beard

  1. I sharpen and shape carefully and flat.  Then I have strop routine.  Does that round or bevel the final edge?

    Then as needed a resharpen not so carefully.  I make sure each stage I use in resharpening goes fully to the edge.  But I use as few stages as I can get away with. And each time I use the strop.  I think these resharpenings probably do bevel the edge some.

    When it does fell right anymore, then I flatten again. Etc.

  2. 26 minutes ago, Three13 said:

    I have wondered whether Zanotti might have descended from Zanetto, but figure that’ll remain a mystery for the ages.

    The story of Zanetto's family seems quite confusing. Depending on what you read, Zanetto is a family name name, or just a name associated with the one member of the family.

    Pellegrino, Micheli, and Zanetto are all names associated.  The correct way to associate the names to family seems very muddy.  At any rate, it seems there where 2 generations making in Brescia, 1 generation working before the mid 1500 examples we have.  And it seems possible that both generations made cellos and violas in Brescia before Andrea Amati invented the size range of the Baroque violin family based on a Brescian viola starting point.

    You can see that the first style of A Amati soundholes are exactly the Zanetto geometry.  Andrea's later holes are still that geometry, but with straight wing cuts from the eyes added.

  3. 2 hours ago, Three13 said:

    A Zanotti! He’s my favorite mystery soldier in the Cremonese fiddle mafia. I’d love to know more about him - clearly trained by an Amati or a Guarneri, claimed to be a student of Girolamo Amati, but sort of pops up to take over when Pietro I dies. Anybody know much more about him?

    I wonder about the not-da Salo. I think the fancy 5-ply purfling is a clue. I sort of want to pretend Tony S or his former employer did the fancy carving.

    Not quite.  That family hails from Brescia.  And there is better cause to believe that Andrea Amati started by copying their work than the other way around.

     

  4. So, one thing that puzzles me is how violin making ended up using the term 'ground' in its own independent way.

    The term obviously relates to the idea of a 'ground' in the painters world.  But violin making uses the term very differently.

    In basically all the arts touched on in Cennini's book, ground means one clear explicit thing: a layer of whiting particles laid down before the coloring and finishing proper.

    These grounds always consisted of a physical layer of particles, and they weren't necessarily the first thing to contact the substrate of a work.

    But violin makers tend to use the word 'ground' to refer to the first things to contact the wood.  And we carry this to such an extreme as to not neccesarily call a layer with particles sitting just on the wood 'ground'.

    For Cennini and his descriptions of artisan practices, a particulate layer sitting right at the wood, that would be called the 'ground'.

    It's rather confusing.  

    Things that Cennini mentions as in various circumstances as comming before the actual 'grounds': stains, mordants, gross filling before freacos with straw or brick dust, soaking with linseed for waterproofing or gross cohesion, sizing.

    How to make things transparent is also mentioned in several contexts.  Penetration with linseed is the primary method. But it's also mentioned that varnishes can be very potent and make things transparent.

    And running throughout, tooth seems a major concern both in sizes and in grounds.  Laying down not just a smooth surface, but an even tooth.

    Now, even in 1580, a violin maker's concerns might have diverged from the general artisan norms.  But still, on some level I would expect a violin maker's ways to be as consistent with the larger arts as say a leather worker's or a guilder's.

    From the context of Cennini, I would expect that the starting point for an instrument maker in 1450 or 1500 would be the idea of 1) wood prep, 2) a typical artisan mineral ground made transparent with penetration by oil or similar, 3) primary color work, 4) protective varnishing.

     

    To complicate things, the first generations of Cremona making sit amid the general arts transition from protein binders and water solvent, to oil binders and spirits of turpentine solvent.  And the later periods of Cremona making run into the rise of alcohol solvents and related materials.

    Now, since Cremona violin making witnessed a change in the availability of solvents, their ideas of preparing the wood, preparing the ground or tooth, working the main color, and protecting with varnish might have evolved.

    But, their starting point would I believe most likely have been the historically obvious one.  And, I believe that's exactly what we're seeing for example in A. Guarneri cello finish that was analyzed with a high degree of spatial accuracy.

    I also believe it like that a maker at the time would have identified the transparent mineral layer sitting above and on the wood as the 'ground'.  And that the oil/balsaam and stain hitting the wood first, what we call 'ground' today would have been called preparation back then.

     

    Ideas to consider...

     

  5. 11 hours ago, Wood Butcher said:

    I often wondered if the old makers reserved the summer months for varnishing, when the warmer and drier weather would surely be an asset.
    Rather than today’s system of make an instrument, then varnish it immediately.

    I know I don't time by the seasons.  I live where there is lots of sun around the corner for most of the year.  I avoid finishing when the weather is actually bad.  And at times that could mean waiting 6 weeks.  But it would never mean waiting 3 months.   But also, I don't approach finishing as something I expect to take days.  I expect it to take weeks or months in its full footprint.

  6. 6 hours ago, Michael_Molnar said:

    Very nice. Any comment about the “kink” above the bass f-hole?

     

    Just that he worked rough and raw to extent we don't accept today.

    Also, I suspect that somehow some of that roughness might have been burnished or conpressed down at the time, and then pulled back up later.  But that is completely unsubstantiated speculation.

  7. Yeah. I didn't say unaided drying is a good idea, or remotely reasonable in time length.

    But if we're talking science and evidence and being accurate with statements, then UV/sun are aides to drying, not essentials to drying.

     

    Me, I like using the sun to dry finishes.  It pleases me.

  8. 12 hours ago, Strad O Various Jr. said:

    I am insisting that anyone that has ever used turpine, rosin/oil varnishes knows that they will not dry without UV light,and in Stradivari's time that meant direct sunlight, not just heat.

    One questions whether you have any experience varnishing violins at all?

    Light and UV are catalysts for drying, they help.  But, drying oils and varnishes should dry eventually anyway.

    Likewise, metalic ions, particle content, and even startch can all aide drying. But none are strictly necessary, just helpful.

     

  9. 55 minutes ago, Rue said:

    So then..."black" violins are a result of:

    A ) Fashion/trend/religion

    B ) Varnish cooked in an iron pot (therefore possibly accidental - since they might not have known the varnish would darken THAT much over time)

    C ) Soot deliberately added to the varnish to "blacken" it...and...

    D) Any/all of the above!

    Not accidental.  It's deliberate.  Two main groups.  The Vienna black instruments.  And as an alternate finish in some cottage industry stuff.

  10. There are many things to talk about in sound holes.  The basic geometry is stable from the Brothers Amati updating their father's sound hole geometry until final late Del Gesu makes changes in the arcs extending out from the eyes.

    But there's lots of subtle tinkering in applying the geometry through the generations of Cremona makers. 

    I say sound holes because across the broader history of N Italian bowed strings, the early style f hole style of A Amati and Zanetto is exactly the C hole shape geometry with the lower half of the C flipped around symmetrically.

  11. 1 hour ago, Peter K-G said:

    These US? Enlish terms still bothers me:

    Resin,rosin,balsam, gum, turp...bla, bla ....

    What's balsam? turp? (extract of gum, rosin,resin, turp... ???)

    It should not be this difficult?

    In Swedish it's called kåda, when it is slowely running from the pine or spruce trees. Kåda becomes hartz when it's solid and the turps have evaporated.

    So, what's balsam other than gum or "kåda"

    Baalsaam >> Honey thick still flowing sap very close to as it comes from a tree.

    Resin >> Something solid that comes that way usually fairly directly from a tree.  Examples being mastic tears, or Sandarac.

    Rosin >> A balsaam like pine, spruce, or larch sap, that has been cooked to drive away the volatile solvent components living a solid resin like material.

     

    Turpentine is complicated.  It started of meaning specifically the sap/balsaam from the Terebinth trees on Chios.  Then it became a general term for thick balsaams.  At that time, Larch Balsaam from the PO region became an acceptable substitute for Terebinth balsaam, becoming known as Venice Turpentine.   Then as things continued, the recollect spirits from converting saps into rosins became an increasingly important and available solvent.  And, the source saps diversified to mean any 'marine stores' conifer. Whatever the sap, the distilled solvent is still properly known as Spirits of Turpentine.  But in modern usage, the word turpentine is assumed to mean the spirits.

  12. And again, these details mean that we only have a limited suggestion that Cremona makers used sun light cure varnish.

    So, again, we have only a likelyhood instead of a certainty.  Though we do have a certain of science that sunlight indeed does help dry oil paintings and cure oil varnishes.

     

    And again, we still have zero evidence against using sunlight now, or against using sunlight historically.

     

    Translation for Sospiri:

    The evidence supporting the idea that Strad used Sunlight to cure varnishes is limited and indirect.

    The evidence denying he used Sunlight is nonexistent.

  13. 29 minutes ago, sospiri said:

    Now write that the other way around and see how it looks?

    Three points of evidence suggesting that he likely did put instruments in the Sun, and that it is a good practice with oil varnishes.

    You have alternately ignored and disparaged those points.  Ignoring them earns disrepect but nothing else.  Disparaging the evidence yields agreement that the case for using Sun isn't iron clad.

    But you have present no evidence at all against using Sun light.

    Score:

    For Sunlight:  likely used, but not certain

    Against Sunlight: No evidence.

  14. 39 minutes ago, sospiri said:

    Yes. I think it's a waste of time. Did you read the comments I made yesterday? Did you understand them?

    You are not making a good case.

    I see zero evidence presented to say either Strad didn't put violins in the sun, nor that modern maker's should avoid it.

     

     

  15. 5 minutes ago, sospiri said:

    Do you a particular interest in the subject?

    Again, ignoring or pushing evidence contrary to your position is not in itself evidence for a position.

     

    Do you have any evidence at all against putting instruments in the sun?

  16. 1 hour ago, GeorgeH said:

    I am curious about the context of this statement.

    Was Stradivari talking about sunlight or solar heat?

    Was he for-certain writing about "bought to perfection" in the varnishing stage of making? Or at an earlier stage?

    Would (is) it difficult for a maker to achieve uniform curing of varnish using just sunlight? It seems to this non-maker that it would be difficult to get sunlight uniformly into all the nooks and crannies of a violin. On the other hand, sitting a violin in the warm sun could cause the seams to open. 

    No. The context is not fully clear.  Nor is it about new making.

    Have you never set instruments out in the sun?  I do this as much as opportunity allows in my new making.  I use to worry.  I no longer do.  I wouldn't put strung onstruments, or someone else's instrument in the sun.  By I've had any bad consequence in putting my instruments in the sun. (Bright sunny Santa Barbara.)

  17. 51 minutes ago, sospiri said:

    Read my earlier comments. 

    What the....?

    You acknowledge no evidence to support yes or no on the question of sunlight.

    Yet you seem to be sure the answer is no?  What is yout evidence?

     

    People are telling you: 1) there is a letter to a repair customer saying sunlight is needed to bring the finish to peefection.  2) science and experience show that UV/sunshine help cure oil varnish.  3) there was a covered rooftop patio on Strad's building which tradition claims was used for sunning and drying instruments.

    But you acknowledge none of these points.

    Here we are in a thread about evidence.  It would reasonable to assery that the evidence isn't fully conslusive.  We can't be certain.

    But to jump to opposite is unreasonable.

    You don't know he didn't sun instruments in the back yard or on the roof patio.

  18. 5 hours ago, ctanzio said:

    Loss of transparency is due to the production of materials that reflect light before it reaches the wood surface. Good quality, dewaxed shellac and alcohol soluble resins do not have such chemical reactions due to aging.

    One can find spectacular French polished furniture in museums that maintain their clarity of finish a great many years after they were initially polished.

    One can also find pieces with oil varnishes that had unstable pigments added that aged into a dark, opaque paint over the years.

    We humans have a proclivity for inductive reasoning: reaching broad generalizations based on a few observations. I have fallen victim to this more times than I care to admit. 

    I'm not saying spirit varnishes always fail, and I'm not saying they are chemically unstable at all.

    I am saying they tend to fail in the direction of drying out.  And, because of this they can, sometimes, get milky or less clear over time.

    Every medium presents challenges.  And we always need to work balancing completing factors.

     

     

  19. Application techniques are everything.

    There certainly are non classical examples, including some Vuillaumes, where it appears that oil has somehow diffused color in an odd way.  But this is only something that can happen under the wrong circumstances.  It is not something that generally happens with every use of oil.

    The main thing to realize is oils and many balsaams will have an aspect of wetting that continues active to some degree for a very long time -- as in years to centuries.

    Wetting, in a small limitied degree, will aide transparency of particles it reaches, and wood structure it reaches.  It can also pull some stains and very fine pigments with it into wood structure by capillary action.  These things are entirely good in small doses, and bad if too free and extensive.   

    In contrast, spirit borne material will loose mobility as the solvent more and more completely leaves. If a spirit borne mix doesn't have enough oily/balsaam component, this drying can reduce transparency over time.

    Good balance is always needed.  

     

  20. 2 hours ago, sospiri said:

    Go on then give me the quote?

    Without misinterpretation.

    There's a letter.

    And, sunlight is nature's UV light box.  UV stimulates polymerization in linseed oil ams drying oil varnishes.

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