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Danube Fiddler

The ground ( sealing) of the great masters - which was it ?

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5 minutes ago, Danube Fiddler said:

 

I think, in classical times an important problem of shellac could have been, that alcohol mostly was not available in the wanted concentration of 96+ % and possibly this was a real problem particularly in the use of shellac, which has some watersoluble contents - only an idea.....

I would disagree with that.  Alcohol has a long history of distillation.  

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8 minutes ago, MikeC said:

I would disagree with that.  Alcohol has a long history of distillation.  

Yes. It would not have been difficult to reach proofs up to 175 with the types of still available during the classical period of making. Been there, done that.

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9 minutes ago, MikeC said:

I would disagree with that.  Alcohol has a long history of distillation.  

Yes, I also assume so - but the absolute limit by destillation, so far I know, is 96 %. How difficult it is, to only reach this limit, I don´t know ( I could imagine, that you have to distill in an extremly low-humidity artificial environment). To concentrate more, there are needed very hygroscopic salts. 

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16 minutes ago, MikeC said:

I would disagree with that.  Alcohol has a long history of distillation.  

There could have been some more problems with shellac. In my experience, its properties can change a lot by different ways of treatenings or even storing, no to speak of differences caused by the processes of purification of the original natural product. May be that in classical times the properties and behaviour of your current shellac- product were difficult to foresee.

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7 minutes ago, JacksonMaberry said:

As I have said, making ethanol that is concentrated enough to dissolve and apply shellac is possible with a simple pot still. I have done it myself. 

This is not the question. The question is, whether there will be solved some watersoluble parts of the available lac-products resulting in some difficulties. We know, that shellac-polished furniture are recommended to avoid water - contact. This water - contact on violins is produced just by breath and sweat. 

May be, there were other reasons for avoiding shellac on violins in the classical time - I don´t know them. Eventually shellac was just more expensive than the resins, obviously used by the makers ( these seem to mostly not have been of oriental origin like sandarac, dammar, (mastic). Although available and used for other purpuses, the oriental resins seem to not have been in extended use by classical makers. 

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1 minute ago, joerobson said:

If we are still discussing the Cremonese Ground, then shellac is excluded.  It remains soluble in alcohol.

on we go,

Joe

I would like to go on discussing the Cremonese ground rather than looking for reasons, why shellac was not the Cremonese ground.

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In my sight of the state of research following seems quite clear

- at the moment ( after 300+ years) many intracellular spaces seem to be filled mostly by dried oil or oil-varnish

- at the moment ( after 300 years of aging and many thousands of hours of light/oxygen -exposition) many cell-walls very near the wood-surface are dark-colored ( in UV ) at least in G.B. Guadagnini - violins. These areas of colored cell-walls have no soft transition to areas of brighter cell-walls -they are sharply limited !

- in some bigger vessels/rays with surface-contact were found a lot of particulates 

- B&G found traces of proteins, not filling spaces, but eventually covering the cell-walls near the surface

- a highly protecting layer covering and protecting the inner surfaces of the wood-pores, but not filling them - and additional covering and protecting the outer limits of wood-fibers, was not identified as a clear defined and limited layer by science until now, so far as I know. However if it would really exist, then according to the current state of research it should be a proteinous layer. The observation of a high-protective layer is similar to observations told by Sacconi.

So, what is probable ?    I.m.o. this could be  :  

1) a first applied slight protein-application eventually in combination with a predone application of a tannic substance to transform the proteins into a not-soluble form

2) a mineral filling of the bigger pores like vessels and rays. Possibly rubbed into the wood for its alone or in combination with a small amout of oil or in the way of shellac-ground with a highly thinned spirit-resin solution

3) eventually now a pure oil-application not penetrating so much because of 1) and 2) and then sun-drying/coloring

or directly

4) application of the surface-layer building (colored) varnish

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2 hours ago, Danube Fiddler said:

Yes, I also assume so - but the absolute limit by destillation, so far I know, is 96 %. How difficult it is, to only reach this limit, I don´t know ( I could imagine, that you have to distill in an extremly low-humidity artificial environment). To concentrate more, there are needed very hygroscopic salts. 

Alcohol becomes azeotropic at higher percentages causing it to become very difficult to seperate the two in a conventional still. 96% is about the highest limit that can be obtained without special conditions.

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used to use spirit varnish rub on rub off ..Like Karate Kid..now I'm concerned if this can be shipped to me through Canadian Mails...I have a product labelled "oil primer" and this raises the question so clearly presented by the experts above... whether it will correctly seal/size the wood..I'll contact the supplier Lemuel in Ontario and see if he can send me spirit varnish through the mails (then I could use it as ground and follow with my usual clear oil varnish with various color extracts

 

Advice would be appreciated..Chanot

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On 7/6/2018 at 2:36 PM, chanot said:

used to use spirit varnish rub on rub off ..Like Karate Kid..now I'm concerned if this can be shipped to me through Canadian Mails...I have a product labelled "oil primer" and this raises the question so clearly presented by the experts above... whether it will correctly seal/size the wood..I'll contact the supplier Lemuel in Ontario and see if he can send me spirit varnish through the mails (then I could use it as ground and follow with my usual clear oil varnish with various color extracts

 

Advice would be appreciated..Chanot

I ship all materials to Canada all the time.

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On 7/3/2018 at 4:36 PM, sospiri said:

Davide, my experience is different to yours. I can get the oil to dry hard enough to resist scratching by fingernails. I would say that is hard enough. And this can happen in  few days too.

I also believe this enhances both tone and playability because it improves the responsiveness of the instrument due to the resilience of the dried oil. In this regard I agree with what many have been saying for at least 150 years. 

 

It's hard for me to believe this, because this never happened to me in all my oil drying tests.

Obviously I have no reason to doubt your experience, but simply I've never met an oil that behaved as you say.
Would you be so kind as to tell me how did you get a similar result?
I mean how to get an oil that when dry becomes so brittle as to behave like a hard rosin-like resin and that it remains so over time,
if I understand that is this what you mean?

 

 

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On 7/6/2018 at 12:00 PM, joerobson said:

If we are still discussing the Cremonese Ground, then shellac is excluded.  It remains soluble in alcohol.

on we go,

Joe

A restorer I know told me once of an  instrument's varnish he had analysed. The lab confirmed it was 100% shellac, but he found it totally insoluble in alcohol. I've heard from multiple sources that shellac looses solubility with age. 

Of course, I don't think shellac could have been the Cremonese ground, but I don't think it's solubility is what rules it out. 

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5 hours ago, Joey Naeger said:

A restorer I know told me once of an  instrument's varnish he had analysed. The lab confirmed it was 100% shellac, but he found it totally insoluble in alcohol. I've heard from multiple sources that shellac looses solubility with age.

That's interesting, particularly as linseed oil gains solubility in alcohol with age.

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Instead of the solubility, which could be different depending on the treatments that shellac has undergone (for example the natural raw and not chemically treated shellac, remains soluble for an indefinite time in my experience) my concern is the UV fluorescence, which is quite different from the whitish yellow of the ground of the ancient instruments.

This does not mean that shellac does not work well acoustically (in fact it works well), only that it is not authentic for those who worry about this.

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8 hours ago, Joey Naeger said:

A restorer I know told me once of an  instrument's varnish he had analysed. The lab confirmed it was 100% shellac, but he found it totally insoluble in alcohol. I've heard from multiple sources that shellac looses solubility with age. 

Of course, I don't think shellac could have been the Cremonese ground, but I don't think it's solubility is what rules it out. 

I don`t use shellac as a ground, for now, but regarding solubility only, when I was restoring 1796Giovanni Battista Fabricatore mandolin, I had a chance to put one of the already chiped pieces of red mastik, that was surounding the mother of pearl and tortoise shell inlays in 96% alcohol and left it there so long that I forgot about it. After a few months I eventualy took that piece out and it was still almost as it was, hard piece of mastic.

Research on 10 early Neapolitan mandolins, Vinnaccia, Fabriatore, Filano.... identified the mastic as a shellac. Sometimes just that and sometimes with added vulcanic ash or other minerals . If the research can be trusted, and I can` t say yes or no, than age of shellac may have  something to do  with solubility of aged shellac.

 

A link to a short version:

  https://www.springer.com/gp/about-springer/media/research-news/all-english-research-news/first-study-of--golden-age--mandolins-unlocks-secrets-of-their-beauty/41810

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Also the permanence of shellac in the solvent (aged varnish in liquid state) can change it chemically and change the solubility, it is not just a matter of aging.

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13 hours ago, Joey Naeger said:

A restorer I know told me once of an  instrument's varnish he had analysed. The lab confirmed it was 100% shellac, but he found it totally insoluble in alcohol. I've heard from multiple sources that shellac looses solubility with age. 

Of course, I don't think shellac could have been the Cremonese ground, but I don't think it's solubility is what rules it out. 

I agree with this,  Also linseed oil does become alcohol soluble which rules it out as the ground,  unless the ground isn't really what you think it is.  

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2 hours ago, MikeC said:

I agree with this,  Also linseed oil does become alcohol soluble which rules it out as the ground,  unless the ground isn't really what you think it is.  

1) I don´t know if it is allowed to claim a general development of dried linseed oil into an alcohol-soluble form, since there are many different ways to pretreat the oil and different ways of cooking/sun-drying and different ways of using driers and may be further differences in exposition to direct or indirect sun-light. I would not dare to state a general rule about later conditions of drying oil without having done hundreds of experiments and waiting for at least decades - especially since the process of oil-drying is not completely understood by science according to wikipedia - infos.

2) the claim, that the Cremonese ground is not (alcohol-)soluble, was made by Joe Robson and probably matches earlier claims of Sacconi. However I don´t know any matching claims by Echard or Brandmair. May be, a lot of restorers made the experience of a high-protective film beeing located directly on the wood-fibres, but not filling the pores. 

3) linseed oil may not have been the very first application on the wood, done by the Cremonese and others - but i.m.o. it is not ruled out as "the ground" in the sense of a filler. The opposite seems to have been quite surely proved : It was the filler ! The only question seems to be, if it was the filler for its alone ( Echard et al ) or in combination with resin as oil-varnish ( Brandmair ). This is state of research, isn´t it ?

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1 hour ago, Danube Fiddler said:

1) I don´t know if it is allowed to claim a general development of dried linseed oil into an alcohol-soluble form, since there are many different ways to pretreat the oil and different ways of cooking/sun-drying and different ways of using driers and may be further differences in exposition to direct or indirect sun-light. I would not dare to state a general rule about later conditions of drying oil without having done hundreds of experiments and waiting for at least decades - especially since the process of oil-drying is not completely understood by science according to wikipedia - infos.

2) the claim, that the Cremonese ground is not (alcohol-)soluble, was made by Joe Robson and probably matches earlier claims of Sacconi. However I don´t know any matching claims by Echard or Brandmair. May be, a lot of restorers made the experience of a high-protective film beeing located directly on the wood-fibres, but not filling the pores. 

 

1) Agreed.

2) I have only one experience with alcohol on the ground of a rather pristine and original and largely un-retouched Strad. The musician had accidentally laid it on an alcohol rag he had been using to clean the strings. There did not appear to be any ground left. With less original instruments, or those which have a larger proportion of replacement varnish or filler, outcomes could be all over the place.

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On 7/5/2018 at 7:36 AM, sospiri said:

Given that the layer of shellac would have to be very thin to act as a sealer because of its inflexibility, I don't see how you can make such an assertion?

Where did you get the idea that shellac is inflexible? You have never used it in a what that really tests its flexibility, I"m guessing.

Joe R--as for remaining soluble in alcohol, you should ask restorers who are familiar with restoring old Hill retouch jobs from when they used shellac. .  .  . they'll have some interesting stories to tell you, if they admit them. :-)

However, I am with people who say it's not traditional. I was only commenting that it worked. And I believe David, above, also.

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21 hours ago, David Burgess said:

1) Agreed.

2) I have only one experience with alcohol on the ground of a rather pristine and original and largely un-retouched Strad. The musician had accidentally laid it on an alcohol rag he had been using to clean the strings. There did not appear to be any ground left. With less original instruments, or those which have a larger proportion of replacement varnish or filler, outcomes could be all over the place.

So the original ground is alcohol soluble. 

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One photo that has made an impression on me is an endoscope image of the interior of the Del Geu Cannone. it shows drip marks from the F holes of a thin colored liquid which I’m assuming is from Del Gesu’s hand.

https://www.google.com/search?q=il+cannone+endoscope&rlz=1C9BKJA_enUS786US787&oq=il+cannone+endoscope&aqs=chrome..69i57.15392j1j4&hl=en-US&sourceid=chrome-mobile&ie=UTF-8#imgrc=YMAJkdCLqJ0QRM:

 

oded

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