Stradivari's Ground

[Johnmasters]

He's said previously that he never got it to work.

I'm thinking it's either a gum, or, since he may be using it in the oil, some type of soap?

Soaps are certain surfactants. Detergent is a more common name, detergent motor oil has an oil-soluable soap. I changed my mind about lecithin recently. Like three or four days ago. One of the phospholipids has the root "lino" in it. See lecithin in Wikipedia. You can guess where this stuff comes from. Linen.

Gums, oils, etc are not going to have two different kinds of ends. See the molecular structure of phospholipids.

[Michael_Molnar]

... .

It isn't any more difficult than making chocolate milk (which also contain emulsifying agents) IMHO

Oded

I guess John told you about how important it is to get one of those milk shake makers on eBay. I got one and it's wonderful for preparing emulsions and shakes.

Mike

[Mauricio]

Before, I discarded the idea after trying to dissolve it in water. That was a long time ago. It is oil soluable.

Thanks, I was under the impression that a surfactant had to be soluble in both phases.

I was going to try to earn a "good for you" with coconut or corn...or risk borax or glycerin.

[Wm. Johnston]

Very good!

Now, HANDS UP ALL THOSE YOU CAN LOOK AT A VIOLIN AND SAY WHETHER IT HAS A CREMONESE GROUND OR NOT.

If you truthfully can, then either you already have a lucrative career in violin authentication or such a career awaits you.

Glenn

Based on photos? You can't be serious. If you think this is a cremonese-like ground then there are many places in this country where you can see authentic examples for comparison. Be sure to take the new sample if you visit so you can compare them under identical lighting. It's a simple test to perform. If they look alike then that is a decent first step towards saying that you have the right ground.

[David Tseng]

Very good!

Now, HANDS UP ALL THOSE YOU CAN LOOK AT A VIOLIN AND SAY WHETHER IT HAS A CREMONESE GROUND OR NOT.

If you truthfully can, then either you already have a lucrative career in violin authentication or such a career awaits you.

Glenn

The ground, if it is done properly, should not be visible. Both calcite and silica all disappear after one coat of oil varnish. The wood of all the Strad I've seen is quite clean almost no color. In those areas where varnish has worn out, such as the back of scroll, the wood remains clean. Now the so-called ground has two components: 1. the outer wood pore filler/ leveling coat, and 2. whatever soaked into the wood. Which is more important to tone or both would have to be proved by the expert makers.

[Wm. Johnston]

"Good for you!" I have had it around a dozen years. I went to Span-80 but decided finally that the main thrust of the whole argument had to be something doable by ancient workers.

But then you use it with a wear resistant varnish unlike the one that the "ancients" used?

[Johnmasters]

Thanks, I was under the impression that a surfactant had to be soluble in both phases.

I was going to try to earn a "good for you" with coconut or corn...or risk borax or glycerin.

I suppose it depends on how much of the molecule is hydrophilic and how much is hydrophobic. The phospholipids seem lop-sided if you look at the illustration. The long chains are fatty acids or similar. If the HLB was more like 10, instead of 5, maybe it would be soluable in both phases.

http://en.wikipedia.org/wiki/Lecithin

The phosphorus and oxygens are a small unit at the top. No oils such as coconut, corn, or any other seed oil by itself is a surfactant. But the plant has to transport the oils somehow, and likely it is dragged around the ciruclation system as some kind of emulsion. Seed oils use lecithin which is really a collection of related things. An egg yolk has lecithin to keep fats in an emulsion. Also, there is a protetive colloid in the yolk, albumen of the same sort as is in the white.

I purposely tried to steer away from eggyolk. Nature likely has supplied just about as much lecithin as is need for it to work out. Emulsions can be made using egg yolk, but likely it would take a lot of yolk. By the time you had a working emulsion, you would also have a lot of staturated fats which may not be a good thing for an oil varnish. (Drying oils are poly-unstaturated).

Borax has no fat soluable component. Glycerin is symmetrical so it would not be useful in any case.

A smile, handshake, and thanks for thinking about it.

[Johnmasters]

Very good!

Now, HANDS UP ALL THOSE YOU CAN LOOK AT A VIOLIN AND SAY WHETHER IT HAS A CREMONESE GROUND OR NOT.

If you truthfully can, then either you already have a lucrative career in violin authentication or such a career awaits you.

Glenn

Thanks... that leads to something else I would like to say.... The chemistry of any possible Strad emulsion is not important as I see it. Any suitable surfactant will give a similar result. Any protective colloid will work, if it works, period. I prefer casein. Any mineral will work to the extent that it is an AGRAGATE. Silicates are good because they bond to nearly everything.

The emulsion is a physical construct, not a chemical one. The upper violin was done with West System 406 and Span-80. I knew I would convince nobody if I did not have a plausible recreation with old materials. Well, you others have found a number of possible minerals. Lecithin is a very good surfactant. And anybody can make casein. So there it is.

[Johnmasters]

But then you use it with a wear resistant varnish unlike the one that the "ancients" used?

Well of course I do. I want wear resistance. Why immitate the "ancients"? Why do YOU immitate them ??? If emulsions were used, I just wanted to show what they could have done, these ancients. I like my varnish and I will like the later ones better. The total varnish with glaze in the top photo is very thin. It can be kept out of the wood too. That is all that is required isn't it?

[cbouts]

It's hard to tell from your photos if your ground looks traditional - there are some optic effects that Strads and Del Gesus have in person where things change from one side of the room and in different light. There is a soft clarity but yet gentle translucence and some effects with distance to consider. Also diffused light shows different details compared to direct sunlight (or camera flash).

Air brushing often brings a problem with "onion peeling" where the surface is cratered like an orange. This can also provide some optic problems with not having layers flat.

One particularly nice strad I spent some time with had huge differences between diffused light and in direct sunlight. Others who were with me were pretty blown away how much the ground seemed to control optics. In direct sunlight exposed areas of the ground that had been chipped pretty hard had a apperance much like very dry snow powder falling in sunlight. You could tell the minerals were refracting and reflecting against themselves. In other light this was not apparent at all. Photos can be deceiving and misleading.

Another instrument that was in last week was from 1690 with a gash in the lower bout back plate clearly exposing the ground and down into the wood in all it's glory. It did not match any of my emulsion type samples I had. You could see how the ground was in the wood, and where it stopped, and how thick it was.

Along with that another instrument accompanied it from a very famous modern maker which I was not overly impressed with visually. It was intended to be a strad copy... But the ground was not right.

All that said - this is commenting on visual apperance and not acoustical properties. To hit the nail on the head I think you have to have both worlds. I think folks are coming really close to the Stradivari Ground - since technology is letting us be able to take a very good look at fragments blown up to amazing sizes.

I think emulsions are one approach at applications, but not an end all - much like there are different ways to inlay your purfling.

Be sure to compare your samples to other cremonese makers other than strad - they all used pretty much the same thing, but applicaton was different.

[Wm. Johnston]

Well of course I do. I want wear resistance. Why immitate the "ancients"? Why do YOU immitate them ??? If emulsions were used, I just wanted to show what they could have done, these ancients. I like my varnish and I will like the later ones better. The total varnish with glaze in the top photo is very thin. It can be kept out of the wood too. That is all that is required isn't it?

I imitate them??? I don't think so. Yes I have a varnish which is a nice color and will wear quickly on it's own, but that doesn't mean that I use it on its own. I have also never claimed that it was used by the Italians. It gives a color that comes close enough to theirs for me to be satisfied with it except that I can't make a good red with it, yet. I also know how to apply it evenly with little problems with dust settling on the film but not with methods available to them. I also don't know if you could make it with ingredients available in Italy at that time. I build new violins in my style, I do not immitate them.

[Johnmasters]

It's hard to tell from your photos if your ground looks traditional - there are some optic effects that Strads and Del Gesus have in person where things change from one side of the room and in different light. There is a soft clarity but yet gentle translucence and some effects with distance to consider. Also diffused light shows different details compared to direct sunlight (or camera flash).

There is no flash on the upper picture. There is a lot of movement when changing light angle (Chatoyence?)

Air brushing often brings a problem with "onion peeling" where the surface is cratered like an orange. This can also provide some optic problems with not having layers flat.

The pits on the one violin in the lower picture are not orange peel due to solvent release. Whatever it is, it is an unusual artifact of a fast job. There is no orange peel with either types of spray coatings I use.

One particularly nice strad I spent some time with had huge differences between diffused light and in direct sunlight. Others who were with me were pretty blown away how much the ground seemed to control optics. In direct sunlight exposed areas of the ground that had been chipped pretty hard had a apperance much like very dry snow powder falling in sunlight. You could tell the minerals were refracting and reflecting against themselves. In other light this was not apparent at all. Photos can be deceiving and misleading.

Here, it seems perhaps that there was more mineral than the varnish could wet, or that the varnish was not thin. Perhaps it was an emulsion made with hot ingrediants. That is something to try along with high mineral concentrations.

I did not do anything to select these photos or put my best foot forward. They are just what they are.

Another instrument that was in last week was from 1690 with a gash in the lower bout back plate clearly exposing the ground and down into the wood in all it's glory. It did not match any of my emulsion type samples I had. You could see how the ground was in the wood, and where it stopped, and how thick it was.

What sort of emulsion samples were these? For the sake of the discussion ?

Along with that another instrument accompanied it from a very famous modern maker which I was not overly impressed with visually. It was intended to be a strad copy... But the ground was not right.

All that said - this is commenting on visual apperance and not acoustical properties. To hit the nail on the head I think you have to have both worlds. I think folks are coming really close to the Stradivari Ground - since technology is letting us be able to take a very good look at fragments blown up to amazing sizes.

I think emulsions are one approach at applications, but not an end all - much like there are different ways to inlay your purfling.

Be sure to compare your samples to other cremonese makers other than strad - they all used pretty much the same thing, but applicaton was different.

I am not interested in comparisons. The upper violin photo is of varnish materials that I had used for a long time before I even started to read about mineral grounds, let alone emulsions to limit penetration of wood. I did not change it until recently. I only decided recently to take a working vacation to buy a bunch of white violins and do some more experiments. I have in my mind the memory of a Filius Andreas that was in Columbus a long time. I am damned close to that. I am not a conoisseur, but I like them both.

In other words, I won't be sure to compare to anything else. I am not trying to copy anything. I just want illuinated wood and colors I like. Also, of course, whatever tonal improvements may result directly from these emulsions.

If it was an emulsion at all, these are extreamly flexible. That is why I avoided giving recipes.

[Johnmasters]

I imitate them??? I don't think so. Yes I have a varnish which is a nice color and will wear quickly on it's own, but that doesn't mean that I use it on its own. I have also never claimed that it was used by the Italians. It gives a color that comes close enough to theirs for me to be satisfied with it except that I can't make a good red with it, yet. I also know how to apply it evenly with little problems with dust settling on the film but not with methods available to them. I also don't know if you could make it with ingredients available in Italy at that time. I build new violins in my style, I do not immitate them.

That is good, but you could imitate them if you wanted to learn something in emulsions perhaps? Get rid of dust problems almost completely. Get reds as deep as you want. Get any color you want. Green and Blue are hardly out of the question. It can be done with ingrediants available in Italy.

But why bother with imitation? Get the Italian sound and put on the color you want. If you WERE successful in duplicating what a Strad or ....... looked like when new, you could not sell it any easier. Let's face it. If I thought otherwise, I would not have spilled the beans. Because I know ways to change it. The later experiments are a bit better than the photos.

[GlennYorkPA]

It's hard to tell from your photos if your ground looks traditional - there are some optic effects that Strads and Del Gesus have in person where things change from one side of the room and in different light. There is a soft clarity but yet gentle translucence and some effects with distance to consider. Also diffused light shows different details compared to direct sunlight (or camera flash).

Air brushing often brings a problem with "onion peeling" where the surface is cratered like an orange. This can also provide some optic problems with not having layers flat.

One particularly nice strad I spent some time with had huge differences between diffused light and in direct sunlight. Others who were with me were pretty blown away how much the ground seemed to control optics. In direct sunlight exposed areas of the ground that had been chipped pretty hard had a apperance much like very dry snow powder falling in sunlight. You could tell the minerals were refracting and reflecting against themselves. In other light this was not apparent at all. Photos can be deceiving and misleading.

Another instrument that was in last week was from 1690 with a gash in the lower bout back plate clearly exposing the ground and down into the wood in all it's glory. It did not match any of my emulsion type samples I had. You could see how the ground was in the wood, and where it stopped, and how thick it was.

Along with that another instrument accompanied it from a very famous modern maker which I was not overly impressed with visually. It was intended to be a strad copy... But the ground was not right.

All that said - this is commenting on visual apperance and not acoustical properties. To hit the nail on the head I think you have to have both worlds. I think folks are coming really close to the Stradivari Ground - since technology is letting us be able to take a very good look at fragments blown up to amazing sizes.

I think emulsions are one approach at applications, but not an end all - much like there are different ways to inlay your purfling.

Be sure to compare your samples to other cremonese makers other than strad - they all used pretty much the same thing, but applicaton was different.

Andrew,

It sounds as though you are one of the rare people who can actually determine if a violin has a classic ground just by looking at it.

I must admit that I cannot but most of my viewings of Strads has been through glass cases.

I have also played on several when they have come up at auction and also on the Messiah when one could do that sort of thing but I have always had to rely on the authority of others that these instruments were what they purported to be.

Perhaps, from your comments, the answer is that a quick look in poor lighting is not enough. The violin should be studied under various lighting conditions to appreciate the subtlety of the ground.

Please, is it possible to appreciate the ground if the varnish layer is intact or is it necessary for some of the upper varnish to be absent and the ground damaged to fully appreciate it?

I'm just wondering why the authenticity of some Strads would be disputed if the optical effects of the ground were diagnostic..

Glenn

[David Tseng]

>>I'm just wondering why the authenticity of some Strads would be disputed if the optical effects of the ground were diagnostic..>>

This reminds me the troubles Swiss Authority had using Wood lamp.

Last year when James Ehnes came back to town to play all the Mozart concertos in a church, I and another maker friend had an opportunity to take a good look at the fiddle from the Fulton collection right after rehearsal. Under the stage flood light, I could'nt see any thing unusual from the ground effect. Of course, I am no expert. All I can say is the fiddle is very clean and there is no dark area (which I call "dirty color").

[cbouts]

Short note about my perspective - when I was younger I spent 10 years doing graphic arts, retouching, color proofs exct for photography and other graphic arts. So I might see things differently than others. Shades, hues, layers, reflectivity...fine details stick out to me because I used to make sure that things were reproduced properly.

Diffused natural light shows many things that are rather hidden when in direct sunlight or an incandecent light. If you think about it, incandecent is more yellow, natural light more blue - diffused light has many rays bouncing around and that bounces differently in reflections on the varnish - direct sunlight can often illuminate layers better when you can't see them in diffused.

So to answer your question yeah good lighting makes a big difference. I prefer natural light. Especially when I'm varnishing.

As far as appreciating the ground layer, full varnish or not if you look closely you can see the layers and the differences of refraction between the two. Variations of chatoyancy (cats eye effect). When I see a cremonese instrument I can tell the ground lightly bends the light... in a unique way. I think that is just because over time being around those instruments you get a feel for what the cremonese guys were doing with their wood and varnish.

If you are referring to the authenticity of the Messiah brought up by stewart pollens - i'm not sure that they discussed varnish as much as construction of the instrument itself -( treble f-hole being off- different knife marks inside the instrument in unusual places exct...)

I'm not sure if one could authenticate a cremonese instrument just by diagnosing the ground effects or measuring with some sort of optical device - thicknesses vary - french polishes invade varnish - exct.... but there is a "look" that the cremonese instruments have just like the venetian makers have a look and the naples makers have their own look as well.

Keep in mind - I honestly think the secret of strad was every point of his craftsmanship was well done and thought out - good wood - good arching, good f-hole design, good thicknesses, good rib structures, good varnish... If you had bad wood and "the cremonese" varnish and slapped it on an instrument - I don't think it would be the magic sauce.

I'm still working on a ton of photos putting them together to show how different resins and minerals react in emulsions - or layers - and how chatoyancy can be souped up with different variations together. I think it would be helpful - as melvin said in another thread seeing is believing... Be patient because i'm pretty swamped at the moment and this is a side research project.

[Bruce Tai]

I guess you all know that the Chinese invented porceline centuries before Europe discovered how to recreate it. "Kaolin" is a corruption of the Chinese "top of the mountain." It must be one hell of a corruption, because I asked my Chinese wife what "Kaolin" meant, and she did not know what I was talking about.

This was clay found at the top of the mountain. Perhaps the large particles seeped downhill. It is also used to size magazine glossy paper. It would have been present in Europe by that time. Especially in Germany. I wonder why the German makers did not use it.......

A few things about kaolinite.

First, the minerals in Cremonese grounds are mostly likely potassium aluminum silicate, calcium carbonate, silica and calcium sulfate. Kaolinite is not a primary candidate.

Second. Kaolinite is called "gao ling" stone in Chinese, and China clay is called "gao ling" earth. "Gao ling" means "tall hill." The town of Jing De has been the major production center of Chinese porcelain for over 1000 years. For centuries Jing De supplied the porcelain used by the royal family. 45 kilometers northeast of Jing De, the "Gao Ling" mountain is known for its fine porcelain clay, called "Gao Ling" earth.

[cbouts]

Are there other minerals local to italy that come close to that list? Or something nearby? Something painters used gesso like in quality?

[Johnmasters]

Andrew,

It sounds as though you are one of the rare people who can actually determine if a violin has a classic ground just by looking at it.

I must admit that I cannot but most of my viewings of Strads has been through glass cases.

I have also played on several when they have come up at auction and also on the Messiah when one could do that sort of thing but I have always had to rely on the authority of others that these instruments were what they purported to be.

Perhaps, from your comments, the answer is that a quick look in poor lighting is not enough. The violin should be studied under various lighting conditions to appreciate the subtlety of the ground.

Please, is it possible to appreciate the ground if the varnish layer is intact or is it necessary for some of the upper varnish to be absent and the ground damaged to fully appreciate it?

I'm just wondering why the authenticity of some Strads would be disputed if the optical effects of the ground were diagnostic..

Glenn

There is also the assumption that it makes a difference. It may, but the two biggest issues seem to be that an O/W emulsion fundamentally wets the wood in a different way from other sealers or varnihes. The other issue is that there is an agragate. This is some kind of mineral. Once concentration (percentage per solids) were determined, it seems that the actual mineral type would be much less relevant.

If people remain seated until the precise mineral composition is determined beyond any doubt, they will sit for a long time.

[Johnmasters]

A few things about kaolinite.

First, the minerals in Cremonese grounds are mostly likely potassium aluminum silicate, calcium carbonate, silica and calcium sulfate. Kaolinite is not a primary candidate.

Second. Kaolinite is called "gao ling" stone in Chinese, and China clay is called "gao ling" earth. "Gao ling" means "tall hill." For centuries Jing De supplied the porcelain used by the royal family. The town of Jing De has been the major production center of Chinese porcelain for over 1000 years. 45 kilometers northeast of Jing De, the "Gao Ling" mountain is known for its fine porcelain clay, called "Gao Ling" earth.

Thanks Bruce, no wonder she did not know what I was talking about.

Andrew, if you can actually make a set of photos to illustrate what you mean here, that would be wonderfully instructive.

[Wolfjk]

Hi J Masters,

I have been following this thread with interest from the beggining.

the two biggest issues seem to be that an O/W emulsion fundamentally wets the wood in a different way from other sealers or varnihes. The other issue is that there is an agragate. This is some kind of mineral. Once concentration (percentage per solids) were determined, it seems that the actual mineral type would be much less relevant.

Any emulsion that contains water makes the woodfibres stand up, and the surface of the wood expand. In wood finishing a water/detergent solution is rubbed on, dried and finished with progressively finer abrasive.

The aggregate is there to fill the pores and any scratches or pits.

The instruments in the Ashmolen Museum have no aggregate or any sort of filler on, as the fine scratches and some toolmarks are visible. The ground is probably oil or clear oil varnish. However there is the question of what they used to make the varnish and what they used to prepare the surface befor varnishing?

Cheers Wolfjk

[Bassbow40]

Hi all,

J.Master congr. your varnish is great!

I have been following this thread with interest from the beggining. I'd like to know is your dried ground soluble in some solvent?

Thanks

G.

[Bassbow40]

Johnmaster,

regarding your surfacant could be ox bile?

So aqueas Phase: water, colloid, particoulate.

Oil phase: oil and ox bile

G.

[GlennYorkPA]

Hi J Masters,

Any emulsion that contains water makes the woodfibres stand up, and the surface of the wood expand. In wood finishing a water/detergent solution is rubbed on, dried and finished with progressively finer abrasive.

The aggregate is there to fill the pores and any scratches or pits.

The instruments in the Ashmolen Museum have no aggregate or any sort of filler on, as the fine scratches and some toolmarks are visible. The ground is probably oil or clear oil varnish. However there is the question of what they used to make the varnish and what they used to prepare the surface befor varnishing?

Cheers Wolfjk

Hi Wolfjk,

If your contention that 'The instruments in the Ashmolean Museum have no aggregate or any sort of filler............' the the entire basis of this thread would be undermined.

I think the contention here is that early Cremonese instruments had, not only a filler, but a relatively thick layer containing particles but that the particles are so fine you cannot see them. They are invisible to the naked eye but impart some interesting optical properties that only a few experts with trained eyes, can appreciate.

(BTW, Have they finished the refurbishing of the Hill collection?).

Glenn

[Anders Buen]

Here is a violin I got back from the Wheeling school system. They have had it for 3 years. It shows no wear, but it has been used a bit.

Here are more recent ones.

The newer samples not yet finished have some improvements. I am as yet undecided on using an additional step which illuminates the wood slightly better.

I like that orange yellow colour. Nice work!