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Thin varnish on ground, same place and light, what a difference!

VarnishGroundTest.thumb.JPG.ac840284ae92b60d08884b6a044399b8.JPG

(ps. not trying to compete with Michael, we just happen to be in the same phase, when it comes to varnish testing)

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Hi Peter, 

You can dissolve the bitumen in balsam turpentine (might take a while) I use it almost watery consistent.  After it is dissolved you can add a couple of drops to a little varnish and mix. But be careful,  it is a pretty strong color. 

The madder lake pigment you can mix into varnish with a muller on a glass plate. Maybe add the bitumen at the same time...

You have to experiment a bit to get the desired color,  good luck! 

 

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Thanks,

Madder pigments I have used before like that so that shouldn't be a problem. It will be interesting to see how it turns out. I did promise a different colored violin to my family. They think I'm boring, making same kind of violins over and over again :)

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4 minutes ago, Mike Spencer said:

That's a really nice looking ground you've got. Is your process documented on your website?

Yes, I'm using the same ingredients all the time with some variations. Mixing quark and Kremer pit lime ratio gives different darkness to the wood (PH value is different). Prolonged exposure to UV enhances the color/contrasts even more. Unfortunately there is not much sun this time of the year here, so I mixed a little varnish into the emulsion for darker color

http://www.thestradsound.com/varnish

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Fjodor,

This is amazing stuff! 

After only one thin layer I can see that this is going to work, both with my varnish and my hand varnishing technique.

It's transparent gives depth to the wood.

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Peter,

Your back arching looks great...very level and fluid. How high? Also I am going to try your quark and lime ground having located the quark here at a market.

Quickly can you describe how the color change happens? I will research this more in depth but would like a quick explanation. Is this similar to casein? I'm not familiar with either...Any problems with cracking using this ground?

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Ipr,

There is no cracking.

I have also read all threads about cracking with this type of ground, which is an effect of casein powder and quick lime. When using fresh cheese curd (Quark) and pit lime (slaked) the emulsion is not aggressive at all. It dries (in minutes) into a glue size that you can control how much you want the varnish to penetrate. 

In this album there is a photo on the reaction which is instant https://goo.gl/photos/BvYG2CYSFytsoGFbA quite light reaction in this example as the quark/lime ratio was ~70/30.

The arch height on the one I'm working on is 17,5 mm. The shape is an effect of optimizing (tuning to a specific frequency and volume). Different wood gives different height and shapes. (= The secret :))

The credit goes to Patrick Kreit and his book. I didn't invent it (I tried for 15 years until the book was published in 2010)

Both arching and varnishing are two important ingredients in copying violin sound.

Now to the office and do some real work ....

 

 

 

 

 

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I just found some info that Patrick posted in an old thread...

Quote from Patrick in that thread...

For the casein to be good, you have to make it yourself from non-fat fromage blanc (fromage frais or curd) and add lime or borax.  

Casein with borax is perfectly translucid. Casein with lime can yield a slightly yellow-green tint but with time, the color disappears.

 

Traces of casein paint have been found in the tomb of Tutankhamen and on the frescoes of Pompeii. Artists used it during the Renaissance and still use it today in tempera painting. It was widely used between the 17th and 19th centuries, when painted furniture was highly popular. In the form of glue, casein can be combined with mineral pigments or with iron oxide, as in artists’ paint.

 

Casein is a glue obtained by mixing curd (fromage blanc or fromage frais) with lime or borax. It is composed of proteins (calcium, phosphoric acid) more complete than those found in gelatins; hence their different characteristics, though both are of animal origin. This binding glue has been known and appreciated for its reliability from Antiquity through the Middle Ages and the construction of cathedrals. It generally creates a very solid, hard film, though breakable on flexible supports.

 

It is ideal for hard, solid surfaces presenting low or high porosity, such as plaster, lime, and especially wood, because it is worm-resistant. Lime-casein lets the surface breathe if need be, but is sufficiently waterproof to resist sponge washing.

 

Borax is a monovalent base that leaves a reversible film as does bone glue. A divalent base such as lime allows the formation of an insoluble casein film. Lime-casein improves water-resistance. It must be applied within one or two hours after preparation. Lime is rot-proof, but powdery and friable, whereas casein is solid and worm-proof.

 

This glue can be used to protect both the inside and outside of the violin body. Casein, an emulsifier, can be combined with linseed oil, castor oil, glucose, or glycerin to make it even more flexible and less permeable, thus dramatically limiting moisture resumption. Once coated with casein, the wood’s moisture content seldom exceeds 9% in the presence of prolonged high ambient humidity. This sizing also has proved to be an acoustic filter, yielding purer sound.

 

Due to wood’s recurrent hygroscopic instability, Italian violin makers exposed their violins to the sun before varnishing them. This procedure stabilizes the frequency of the top and back plates by preventing resumption of moisture at the highest level.

The surface of the wood exposed to sunlight or UV light becomes oxidized. The chemical reaction between the lime-casein coating and the oxidized wood instantaneously gives the latter a fine honey color. It is impossible to imitate this reaction by using other substances. Translucent and practically inalterable, casein accentuates the grain of the wood. The consistency, plasticity, and color of this primer resemble those of the old Italian violins. The advantage of casein is that it is applied cold and is quick-setting.

 

Casein with lime or borax can be mixed with iron oxide (yellow, brown, or red) to give a more intense color to the prime coat before varnishing.

 

Below 12 °C (53.6 °F), casein forms lumps (instead of glue), so it is unsuitable for winter use outdoors or in an unheated workshop. Collective memory must therefore have understandably disregarded casein in favor of bone glue that was easier to use and transport once it appeared on the market.

 

If the lime is old, the reaction with the curd fails to occur. The lime must be heated in a pan so that water evaporates from it. Let the lime cool before using it. Careful: it is practically quick lime!

The curd/heated lime mixture must not be used immediately, or the reaction will be too strong upon application to the wood and will yield a dark brown color. Instead, it must be set aside for approximately 30 minutes to let the quick lime become slaked lime.

 

Test the sizing on maple and fir samples before using it to coat the wood of an instrument. Depending on the reaction time of the casein glue being prepared, the result will be a lovely color of old wood or absolutely translucent sizing. Lime is an aggressive substance, so gloves must be worn while using this sizing in order to reduce the risk of dermatitis on sensitive skin.

Add 5% castor oil, linseed oil, glycerin, or glucose (honey or grape sugar) to the casein to make the size less permeable.

 

The casein can be applied on the wood without previously filling the pores, for it adheres perfectly and uniformly to the surface, thus decreasing anisotropy in the materials, particularly when it is also applied to the interior of the sounding box (including the ribs).

The quality of the violin's sound is enhanced. Casein acts as an acoustic filter. The sound is purer. A silica (quartz) or colloidal silica filler can be added to the casein if prior sealing of the wood pores is not desired.

 

Application of a casein-oil emulsion on wood presents no problems. This size can be applied equally well with a brush or a cloth. Casein size made with hydraulic lime can be used for 1 to 2 hours, whereas with borax, it can be used for approximately 24 hours.

 

Formulation of the casein depends on its use:

 

-          Casein with 10% lime has a pH of 11: vegetal pigments change color.

-          Casein with 45/50% lime has a neutral pH (7): vegetal colors do not change.

-          Casein with 10% borax has a neutral pH (7): vegetal colors do not change.

 

Casein with 10% lime yields a prompt reaction on wood that has been exposed to the sun or to UV light. It gives the wood a lovely, perfectly even, inimitable honey color. Casein is plastic and dries quickly. Another advantage is that it is applied cold. To lower the pH, add a few drops of lime juice or balsamic vinegar.

 

Lime casein sizing should be sanded after 20 minutes’ drying time; borax casein, after 1 hour. The second coat, however, must not be sanded, for it is very thin. It is preferable to apply it with a cloth and rub it in to obtain even distribution without blisters or overlapping marks.

 

Dye can be applied on top of the casein. All dyes used in violin making adhere well to this sizing.

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Glad you found Patrick's post, impossible to explain this any better, I'm practicing different possibilities from that.

Here is another example, done in summertime when it was possible to expose the violin to sun light, no colors added. The best way i can explain the difference to other grounds I have used is that it is Golden (not yellow)

58f734dd4306c_2014-07-1120_18_41.thumb.jpg.179984d3cbb21b896ce5e94518ec5e88.jpg

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3 hours ago, lpr5184 said:

I just found some info that Patrick posted in an old thread...

Quote from Patrick in that thread...

For the casein to be good, you have to make it yourself from non-fat fromage blanc (fromage frais or curd) and add lime or borax.  

Casein with borax is perfectly translucid. Casein with lime can yield a slightly yellow-green tint but with time, the color disappears.

 

Traces of casein paint have been found in the tomb of Tutankhamen and on the frescoes of Pompeii. Artists used it during the Renaissance and still use it today in tempera painting. It was widely used between the 17th and 19th centuries, when painted furniture was highly popular. In the form of glue, casein can be combined with mineral pigments or with iron oxide, as in artists’ paint.

 

Casein is a glue obtained by mixing curd (fromage blanc or fromage frais) with lime or borax. It is composed of proteins (calcium, phosphoric acid) more complete than those found in gelatins; hence their different characteristics, though both are of animal origin. This binding glue has been known and appreciated for its reliability from Antiquity through the Middle Ages and the construction of cathedrals. It generally creates a very solid, hard film, though breakable on flexible supports.

 

It is ideal for hard, solid surfaces presenting low or high porosity, such as plaster, lime, and especially wood, because it is worm-resistant. Lime-casein lets the surface breathe if need be, but is sufficiently waterproof to resist sponge washing.

 

Borax is a monovalent base that leaves a reversible film as does bone glue. A divalent base such as lime allows the formation of an insoluble casein film. Lime-casein improves water-resistance. It must be applied within one or two hours after preparation. Lime is rot-proof, but powdery and friable, whereas casein is solid and worm-proof.

 

This glue can be used to protect both the inside and outside of the violin body. Casein, an emulsifier, can be combined with linseed oil, castor oil, glucose, or glycerin to make it even more flexible and less permeable, thus dramatically limiting moisture resumption. Once coated with casein, the wood’s moisture content seldom exceeds 9% in the presence of prolonged high ambient humidity. This sizing also has proved to be an acoustic filter, yielding purer sound.

 

Due to wood’s recurrent hygroscopic instability, Italian violin makers exposed their violins to the sun before varnishing them. This procedure stabilizes the frequency of the top and back plates by preventing resumption of moisture at the highest level.

The surface of the wood exposed to sunlight or UV light becomes oxidized. The chemical reaction between the lime-casein coating and the oxidized wood instantaneously gives the latter a fine honey color. It is impossible to imitate this reaction by using other substances. Translucent and practically inalterable, casein accentuates the grain of the wood. The consistency, plasticity, and color of this primer resemble those of the old Italian violins. The advantage of casein is that it is applied cold and is quick-setting.

 

Casein with lime or borax can be mixed with iron oxide (yellow, brown, or red) to give a more intense color to the prime coat before varnishing.

 

Below 12 °C (53.6 °F), casein forms lumps (instead of glue), so it is unsuitable for winter use outdoors or in an unheated workshop. Collective memory must therefore have understandably disregarded casein in favor of bone glue that was easier to use and transport once it appeared on the market.

 

If the lime is old, the reaction with the curd fails to occur. The lime must be heated in a pan so that water evaporates from it. Let the lime cool before using it. Careful: it is practically quick lime!

The curd/heated lime mixture must not be used immediately, or the reaction will be too strong upon application to the wood and will yield a dark brown color. Instead, it must be set aside for approximately 30 minutes to let the quick lime become slaked lime.

 

Test the sizing on maple and fir samples before using it to coat the wood of an instrument. Depending on the reaction time of the casein glue being prepared, the result will be a lovely color of old wood or absolutely translucent sizing. Lime is an aggressive substance, so gloves must be worn while using this sizing in order to reduce the risk of dermatitis on sensitive skin.

Add 5% castor oil, linseed oil, glycerin, or glucose (honey or grape sugar) to the casein to make the size less permeable.

 

The casein can be applied on the wood without previously filling the pores, for it adheres perfectly and uniformly to the surface, thus decreasing anisotropy in the materials, particularly when it is also applied to the interior of the sounding box (including the ribs).

The quality of the violin's sound is enhanced. Casein acts as an acoustic filter. The sound is purer. A silica (quartz) or colloidal silica filler can be added to the casein if prior sealing of the wood pores is not desired.

 

Application of a casein-oil emulsion on wood presents no problems. This size can be applied equally well with a brush or a cloth. Casein size made with hydraulic lime can be used for 1 to 2 hours, whereas with borax, it can be used for approximately 24 hours.

 

Formulation of the casein depends on its use:

 

-          Casein with 10% lime has a pH of 11: vegetal pigments change color.

-          Casein with 45/50% lime has a neutral pH (7): vegetal colors do not change.

-          Casein with 10% borax has a neutral pH (7): vegetal colors do not change.

 

Casein with 10% lime yields a prompt reaction on wood that has been exposed to the sun or to UV light. It gives the wood a lovely, perfectly even, inimitable honey color. Casein is plastic and dries quickly. Another advantage is that it is applied cold. To lower the pH, add a few drops of lime juice or balsamic vinegar.

 

Lime casein sizing should be sanded after 20 minutes’ drying time; borax casein, after 1 hour. The second coat, however, must not be sanded, for it is very thin. It is preferable to apply it with a cloth and rub it in to obtain even distribution without blisters or overlapping marks.

 

Dye can be applied on top of the casein. All dyes used in violin making adhere well to this sizing.

I think there are errors in the post by Patrick Kreit. Specifically, regarding whether lime casein is water resistant but borax/casein is not. According to John Masters, it is the other way around. Borax/casein is water resistant.

 

Also, the pH numbers are reversed. 10% lime is more neutral than 50% lime.

Someone please check me on this. Patrick Kreit should be informed of the result.

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There is a lot of information on the Internet on this, for example http://cameo.mfa.org/wiki/Lime_casein

  • Lime casein is a clear, viscous solution that dries to form a water-insoluble film.
  • Lime casein has a high pH (9.0-9.9) compared to ammonium casein (8.0-9.0), and borax casein (7.0-7.8).

My recommendation is to test for your self, from my experince  (not measuring PH) this is true:

  • Casein with 10% lime  ->  change color
  • Casein with 45/50% lime ->  colors do not change

Using fresh cheese curd (Quark) and slaked pit lime weight ratios, which is not the same as casein powder and quick lime weight ratio.

 

 

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It's also very cheap

http://shop.kremerpigments.com/en/fillers-und-building-materials/limes/4894/pit-lime

1 l costs 10 USD (I have used it for 5 years and can use it for 15 more years)

200 g Quark is found in every supermarket 0,70 € (I use a tablespoon the rest I give to our cat)

Try it, if you don't like it eat it (except for the lime). Body builders eat it every day :P (I don't need it because I was born inherently strong)

 

 

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Lime casein is more water resistant but neither are waterproof. Not even commercial casien glues were more than water resistant agaonst modern alternatives

A disturbing feature of applying casein to wood in my experience is that it causes cracks on a long term basis 

 

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Peter, it's looking good!

Fiddlecollector suggested in an other thread to add a tiny bit of glycerin to the casein mix to help prevent cracking, so I did this
on the latest violin I just to feel safer.
The recipe on Peters webpage is also an oil emulsion, so it might behave differently.

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The readymade casein that is marketed is not intended for use as a ground, but only for painting walls and decorating furniture, by adding pigments and linseed oil (the latter is essential to avoid cracking and flaking).

Only casein made with fromage blanc (and lime or borax) can be used in violinmaking. This sizing is very thin, unlikely to crack, and dries in a few minutes. To increase its suppleness and impermeability, it is necessary to add a plasticizer (linseed or castor oil, or glycerine or glucose), which also facilitates application.

Casein (lime or borax), like varnish, is micro-porous.

www.kreitpatrick.com

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