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Jacob

Varnish making

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Rather than continuing the "Seeding" thread, I thought it might be better to start a new one, with the following thoughts offered for comment.

The "firm pill stage" is held by many as prerequisite for a good varnish. However, the original "Marciana" recipe does not mention this, and at least two members of this forum (Melvin Goldsmith and Neil Ertz) apparently don't cook up to that stage.

Gum spirits as a thinner, either during cooking or for subsequent further thinning, is also frequently mentioned as an absolutely vital component of a good oil varnish. However, gum spirits didn't exist during the classical Cremonese period. For one, the Marciana recipe does not call for the addition of gum spirits during cooking (or at the cooling stage).

Cooking the resins for considerable periods of time in order to enhance the color also seems to form an important part of the process advocated by many - except that it is always mentioned that additional coloring matter will need to be added prior to application. So why bother with extra cooking in the first place, espacially if this may ruin the varnish?

Many current recipes call for a cooking temperature of up to 300C, both for the pre-cooking of the resin as well as for the oil/resin cooking. I'm treading on dangerous ground here, but in my personal experience, the higher the temperature, the more the chances of inexplicable varnish faults.

About "testing" a particular concoction: applying to strips of wood instead of to a finished instrument first - that's good, it's a no-brainer. However, if someone goes against conventional wisdom (urban legend?) with a particular recipe, and states that it is still good after five years, how does one answer the question "what will it be like after 50 years?" It would be nice to hear from varnish makers who can attest to the "goodness" of their product after 50 years, but I know I won't care a rat's @ss about what I slapped on a violin when I'm 110 years old (don't worry, I won't get there).

About some of the contritubions in these varnish threads: I think we all respect the fact that some posters may have proprietory knowledge which they do not wish to share publicly, and I, like many others, appreciate their contributions on these topics. May I suggest that care is taken in posting comments which may elicit further inquires compromising a commercial situation, causing further inquires to be snubbed. Firstly, such comments are not helpful at all (since they are no more than teasers), and secondly, it can make further innocent and honest inquires seem to come from delinquent schoolboys too lazy to do their own homework/too stingy to buy their own lunch, when in fact the opposite may be true. In short, one shouldn't open avenues down which one don't want/can't afford to go. It can make other participants in the thread look unnecessarily stupid, and can give some posts a commercial air which I'm sure isn't intended.

Interestingly, I noticed on Keith Hill's website that he is now offering his varnish for sale due to public demand, at prices pretty much comparable to any other commercially available varnish - clear indication that more people are looking for a varnish rather than a recipe. If it were to make financial sense to me I would buy any of the high-end commercial varnishes without question.

I'm very grateful for all the feedback I received in the "Seeding" thread. There are quite a few ideas in there worth pursuing.

Viva Maestronet.

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from doing a google search, references to turpentine go back to the 14th century, turpentine was first used for dry cleaning clothes in 1690, of course the turpentine they used that far back presumably contained a lot higher percentage of tree resins than what we call spirits of turpentine today, most of which is not even turpentine based

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I looked at the 'seeding' thread and I confess I don't understand the concept of cooking varnish to the firm 'pill stage'. Does it have to do with the length of cooking time and the temperature?

The little I know about the Marciana recipe comes from reading Geary Bease's Book 'Classic Italian Violin Varnish' and his article in the Strad published July 1996. In the latter Bease talks about once the resin has been added, increasing the heat until a slight froth or foam appears and cooking the varnish after that until it 'strings well' (about 15 cm). The longer the string, apparently the faster the varnish will drying

apologies in advance if this has been covered before

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from doing a google search, references to turpentine go back to the 14th century, turpentine was first used for dry cleaning clothes in 1690, of course the turpentine they used that far back presumably contained a lot higher percentage of tree resins than what we call spirits of turpentine today, most of which is not even turpentine based

Exactly. I'm talking about "gum spirits" which is called for in many recipes. As far as I can ascertain this is a product which dates from the middle 1700's.

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I looked at the 'seeding' thread and I confess I don't understand the concept of cooking varnish to the firm 'pill stage'. Does it have to do with the length of cooking time and the temperature?

The little I know about the Marciana recipe comes from reading Geary Bease's Book 'Classic Italian Violin Varnish' and his article in the Strad published July 1996. In the latter Bease talks about once the resin has been added, increasing the heat until a slight froth or foam appears and cooking the varnish after that until it 'strings well' (about 15 cm). The longer the string, apparently the faster the varnish will drying

apologies in advance if this has been covered before

"Firm pill" = "strings well".

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"Firm pill" = "strings well".

So I was on the right track.

One further thought ... Bease in another article american Lutherie GAL #18, 1989 refers to an apparatus designed by Leonardo da Vinci to produce essential oils like spike or turpentine. Looks like a device to hold covered alembic pots with a fire underneath. This suggests that some form of turpentine was available ca 1500 as Lyndon notes above.

Chris

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Jacob,

I cooked my last large batch of Bease recipie varnish a long long time, to the point where it is not soluble in turpentine at all, and only disovles with considerable encouragement in alcohol. What happened to the varnish during this extended cooking time, chemically speaking, I don't know, but it's worth noting that something happened !

Good luck with yours.

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Turpentine has been mentioned in medicinal tracts since Roman times...Pliny the Elder if I remember correctly. The earliest surviving text that mentions turpentine in cooking varnish dates circa 1751...though I am certain the use goes back into at least the 16th century. Here is some information: http://www.violinvar.../turpentine.htm.

The drawing comes from a medical tract circa 1620.

Don't rely too heavily on the "ancient recipes" as they seem more like side notes of stuff the varnish maker thought he might forget....the basic stuff was not worthy of the expense of paper and ink. My notes often look similar....the trade of varnish making has a long and deep history and the actual literature is very good. Best advice: take good notes as you cook. If you make something you like, then you will be able to repeat and perhaps refine your efforts.

As far as this thread is concerned, I will be glad to contribute within my comfort zone...you also should know that David B., Kelvin and Oded are accomplished varnish makers.

Joe

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UL,

When the oil and resin are cooked together and a small amount is dropped on a flat cool surface...touch a finger [yeah, it;s hot] to the droplet and pull the finger away...a small thread of varnish will connect the finger and the droplet. The length, shape, and strength of this thread is "pill". A number of varnish characteristics can be controlled by the character of the "pill"...hardness, drying properties, and open time among them. This is a judgement call for the varnish maker...How firm a pill is correct for the varnish I am making?

on we go,

Joe

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I think that Joe has answered the question correctly regarding "pill stage." I know that in my own experience, the issue of pill stage, or more exactly, a pill stage of say six inches was highly influenced by the resin to oil ratio of the varnish I was cooking. With long oil varnishes, pill stage was very hard to achieve. With short oil varnishes, pill stage was very easy to achieve. Perhaps at the moment it seems to be in vogue to have high resin to oil ratios in varnish cooks, with long resin cooks and more solvent, but in my experience, a one to one ratio has always worked well for me.

Kelvin

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Turpentine has been mentioned in medicinal tracts since Roman times...Pliny the Elder if I remember correctly. The earliest surviving text that mentions turpentine in cooking varnish dates circa 1751...though I am certain the use goes back into at least the 16th century. Here is some information: http://www.violinvar.../turpentine.htm.

I offer this extract from William Fultion's "Turpentine Violin Varnish":

The word turpentine is derived from the Latin word terebinthos, the turpentine tree. The turpentine tree is a small European anacardiaceous tree, Pistacia terebinthus, yielding Chian turpentine or terebinth. The resin from this tree had for centuries been used as a varnish or coating material as it will dry into a strong solid film. Antonius Brasasavols, 1500-1555, composed a book on medical simples in 1534, in which he mentions that larch-tree resin (venice turpentine) was sold for terebinth, but that true terebinth was imported in round lumps from Cyprus to Venice. Careful examination of early writings reveals that, with the exception of terebinth, all natural materials from the living tree, now referred to as a pine resin, were called pitch. Burgundy pitch from the Pinacceae Abies, native of Europe, and Venice pitch from the larch-tree are examples.

When the alchemists subjected pitch to dry distillation it yielded two materials which they called rosin and turpentine. As we know, among other uses, rosin was used to impart friction to the hair of bows used with string instruments.

Turpentine, thought of and used today as a paint and varnish thinner, was not used as such during the the 16th and 17th centuries. No mention can be found that the thinning properties of turpentine were recognised until 1773 when Watin first described its use as a thinner in the paint industry.

Turpentine, now known as steam distilled gum turpentine, is produced in many countries of the world. During its production extreme care is taken to assure a water free nonoxidized product. It is essentially a mixture of reactive unsaturated terpene hydrocarbons. When these terpene hydrocarbons are exposed to the air they will polymerize to form terpene resins. This is best illustrated by the fact that turpentine becomes gummy or fatty on standing. The steam distilled dehydrated and bottled product sold today bears little resemblance to the turpentine of the 16th and 17th century. The crude dry alembic of the alchemist assured an aereated product which, upon standing open to the air, quickly became gummy and thick resembling the true terebinth. For this reason it was called turpentine and because of its thick consistency it was not considered a thinner. Until steam dstillation was introduced toward the middle of the 16th* century and until close controls were exercised in storage, the thinning properties of turpentine were non-existent.

* I suspect "16th" to be a misprint. In the context of what preceeds it, it should probably read "18th".

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UL,

When the oil and resin are cooked together and a small amount is dropped on a flat cool surface...touch a finger [yeah, it;s hot] to the droplet and pull the finger away...a small thread of varnish will connect the finger and the droplet. The length, shape, and strength of this thread is "pill". A number of varnish characteristics can be controlled by the character of the "pill"...hardness, drying properties, and open time among them. This is a judgement call for the varnish maker...How firm a pill is correct for the varnish I am making?

on we go,

Joe

Joe ,are you certain about that description of `pill`. Most varnish texts ive read dont mention pill they just mention stringing. To me `pill` is used to describe the texture of confectionaries such as fudge,when cooked properly and dropped in water the fudge is rolled into a small ball or pill. (my wife came from a family of confectioners going back over 150 years) I think this `pill` refering to varnish is a modern term which is a confusing and incorrect term to use. (though i have rolled varnish into small balls) I may be wrong but i only refer to stringing. :)

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Joe ,are you certain about that description of `pill`. Most varnish texts ive read dont mention pill they just mention stringing. To me `pill` is used to describe the texture of confectionaries such as fudge,when cooked properly and dropped in water the fudge is rolled into a small ball or pill. (my wife came from a family of confectioners going back over 150 years) I think this `pill` refering to varnish is a modern term which is a confusing and incorrect term to use. (though i have rolled varnish into small balls) I may be wrong but i only refer to stringing. :)

I agree that the terminology is misleading. The "string" is what one is after, although the ideal length of this string varies a lot from one recipe to another. On occasions when I've overcooked the varnish, the "pill" doesnt' string at all. When the varnish starts stringing, the length of the string changes very quickly, one really has to be on the ball. From a modest length string to a pill that won't string at all can happen inside five minutes at 300C. Obviously at a lower temperature one will have a bit more latitude when to stop cooking.

I didn't mean to speak for Joe, just my impressions...

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When i make varnish i just rub a little bit of it between my finger and thumb and pull them apart to get a string. It is hot but im used to it and must have asbestos finger tips by now. I agree that varnish can start string very early on. I rarely cook my varnish for more than 1 hour. Can understand why some cook for hours and hours.

Same goes for colour of the resin etc... on cooking, it tends to produce the most colour within an hour so dont see any advantage in cooking for alot longer as they always need some pigment or something added at the thickness you put on violins (which is a shame because they long very beautiful in a thick coat with nothing added.)

I usually apply my varnish slightly on the thick side anyway because it always shrink anyway over the years. Ive seen varnish shrink by about 50 % in thickness over only 5 years . So those who put extremely thin varnish on had better hope its still visible after 50 years or so.

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To test stringing I use a piece of wood, away from the heat source.

Last batch was a bit on the lean side and made super long strings.

In his Strad article Bease mentions adding (when varnish has cooled off a little) up to 20% turpentine spirits for impoving brushing quality and to aid decanting.

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First I'd like to thank Jacob for the really interesting thred (or should I say threads) and all for the great posts above.

If I may, on the turps subject....

I don't know about before the 1600's have not read older texts upon these materials much, except for Cennini, and a few other thigs, but from the middle 1600's on I have seen in many different texts the use of a Retort, or an Alembic, same or similar to the one used to distill grappa, and other methods, including water, for distilling what was called, Acqua di Ragia, or Spirito de Ragia, or Spirito di Trementina, ...the juice that escapes from the tree was called Trementina, if cooked by the sun or fire called Ragia or Resina, Pece or Pix. Other texts from the 1600's call the first juice that exudes from a cut in an old Pine tree of Pisseleon (latin) olio di pece in italian, the juice that comes after it before being cooked was called by the merchants Barras, two species, a whiter one called Galipot or incenso bianco, and the other incenso screziato. The Galipot once liquefied with fire and placed in barrels for transportation was called Trementina grossa. and so on......The juice from the Pistacia Terebinthus was called Terebinto.

Venice for some time was a major supplier of the Trementina from the larch trees of Tirol, Veneto, Illiria, Germany, large part of the venetian commerce went through Trieste, and would supply most of Italy and Germany.

As for it's uses on varnishes, a recipe in a book from 1561, by Claudio Ptolomeu and Girolamo Ruscelli, note that it is called Termentina and Acqua di Ragia on this book.

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Carlo,

This range of definitions is what I have also found in the literature.

On the Watin text. The Watin manual is generally considered the compilation of previous texts. [the Watin text includes a section on "Vernis Martin" which is the furniture world's equivalent to the Amati varnish. The originator of this varnish was made varnish maker to the French court in 1723]. Since it was a success financially it was pirated at least 25 times by historical accounts. I think theinformation is largely correct though not original.

One of the interesting and informative aspects of this research is to sift through the language to find

solid meanings. Unfortunately a lot of the old literature is in the form of poor translations into English.

As the original texts may present more insight I am thankful to people like you who will read and provide studies and feed-back on the original materials.

on we go,

Joe

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I know that many makers just use cooked resin/oil finishes, so I would be very interested to read descriptions of the behaviour of these 'varnishes' that are resin/oil versus resin/oil/turpentine (latter added during the cooking).

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Sorry Janito, nothing kills a thread faster than me.

Seriously though....if you are experimenting with such finishes you will need an oil rich mixture and expect to use siccatives to get a cured surface in an acceptable time.

on we go,

Joe

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Sorry Janito, nothing kills a thread faster than me.

No need to apologise. I am expecting to need to use siccatives.

I am interested to know what the cooked-in turpentine is contributing in the oil/resin/turpentine varnish. Brushability, surface texture ????, versus oil/resin that is thinned with a solvent.

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I cook mine without turpentine, and seems to be ok for drying.

Takes 4 hours in the light box to dry to the touch.

I might add a pinch of turpentine and spike oil when mixing it with pigments and also to help application, though.

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But if one uses for example larch/strasbourg turpentine or some balsams in making varnish, and cook at sufficently low temperature, I guess there will still be enough "spirit" of turpentine left so that one can simple add the larch, maybe some other resin and oil and cook it.

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