Varnish Sample...

[JacksonMaberry]

Well made, finely divided lakes are great! Madder lakes especially, since the suite of dyes in the plant is so broad. You can make reds, browns, oranges of almost any hue, in theory. I don't use them myself but I know a lot of top flight makers that do, and to great effect.

[Davide Sora]

1 hour ago, JacksonMaberry said:

Then it isn't rosinate. 

You're right that rosinates are in some way like lakes! But they have a major difference that is pretty important. 

Lakes: dye precipitated onto a metal oxide 

Rosinates: dye precipitated onto a rosin-metal complex.

In fact some systems for making lakes include rosin, so they can perhaps be considered rosinates. For example, I do this for the red madder pigment,  and transparent verdigris has been known since ancient times, probably the first rosinate that has ever been made.

In addition, powdered rosinatas can be used as lakes, simply by mulling them in the varnish instead of cooking them together or by dissolving them in turpentine. I think it was Frank Ravatin who used them that way, and me too.

[charliemaine]

22 minutes ago, Davide Sora said:

In fact some systems for making lakes include rosin, so they can perhaps be considered rosinates. For example, I do this for the red madder pigment,  and transparent verdigris has been known since ancient times, probably the first rosinate that has ever been made.

In addition, powdered rosinatas can be used as lakes, simply by mulling them in the varnish instead of cooking them together or by dissolving them in turpentine. I think it was Frank Ravatin who used them that way, and me too.

Can you explain how you incorporate the rosin into red madder when making a lake? 

The rosinates settle to the bottom of the jar when left to sit. Can this be scraped out of the jar and mulled into a varnish like a lake pigment? 

[JacksonMaberry]

24 minutes ago, Davide Sora said:

In fact some systems for making lakes include rosin, so they can perhaps be considered rosinates. For example, I do this for the red madder pigment,  and transparent verdigris has been known since ancient times, probably the first rosinate that has ever been made.

In addition, powdered rosinatas can be used as lakes, simply by mulling them in the varnish instead of cooking them together or by dissolving them in turpentine. I think it was Frank Ravatin who used them that way, and me too.

Davide, what you're describing is using a rosinate as a pigment. I think of it like squares and rectangles: all squares are rectangles, but not all rectangles are squares.

All rosinates are lakes, but not all lakes are rosinates. 

I wanted to make sure charliemaine understood that, in the most specific sense, there is an important difference between what is conventionally called a lake pigment and a rosinate, so that he didn't try to make a varnish without a resin. 

[JacksonMaberry]

5 minutes ago, charliemaine said:

Can you explain how you incorporate the rosin into red madder when making a lake? 

By making a rosinate. Check my article for a full how to. 

[charliemaine]

42 minutes ago, JacksonMaberry said:

I wanted to make sure charliemaine understood that, in the most specific sense, there is an important difference between what is conventionally called a lake pigment and a rosinate, so that he didn't try to make a varnish without a resin. 

I would like to read your article if you send me the link or point me in the direction. I think I understand the difference now between a lake and a rosinate. A rosinate contains rosin and a lake does not. 

The Ertz pigment is just madder root extract attached to an Alum substrate. No rosin invloved.

Don't worry I definitely would not try making a varnish without resin...

[JacksonMaberry]

Just now, charliemaine said:

I would like to read your article if you send me the link or point me in the direction. I think I understand the difference now between a lake and a rosinate. A rosinate contains rosin and a lake does not. 

The Ertz pigment is just madder root extract attached to an Alum substrate. No rosin invloved.

Don't worry I definitely would not try making a varnish without resin...

Send me your email address please.

[charliemaine]

8 hours ago, JacksonMaberry said:

Send me your email address please.

Appreciate it!  I have a copy of Nunzio's book too but I haven't had the time to read any of it. If your varnish is a 3:2 ratio then I will have to give it a go...that sounds about right to me, durability wise that is. Back when I was making lots of varnish and experimenting I remember reading or asking Brian Lisus about his varnish. If I remember correctly he said that he made his varnish at that time with a 60:40 oil to resin ratio. I found that made a nice varnish for my purposes. I also made nice varnishes using a 1:1 ratio depending on what resin(s) I was using.

I've not used any commercial or homemade 1:1 ratio varnishes that were as brittle as this particular old batch of Nunzio's rosinate. It definitely behaves differently from any 1:1 varnish that I've used. And I've used almost everything out there on the market. 

I do like how well his varnish builds color so quickly and apply's effortlessly. I think if he added more oil it would be an improvement. Sounds like you've made a good choice by changing to a 3:2 ratio.

I will say his amber and copal varnishes are very nice.

[Davide Sora]

15 hours ago, JacksonMaberry said:

Davide, what you're describing is using a rosinate as a pigment. I think of it like squares and rectangles: all squares are rectangles, but not all rectangles are squares.

All rosinates are lakes, but not all lakes are rosinates. 

I wanted to make sure charliemaine understood that, in the most specific sense, there is an important difference between what is conventionally called a lake pigment and a rosinate, so that he didn't try to make a varnish without a resin. 

Yep, thanks for pointing out. In fact, not all rosinates can be effective as a pigment, the presence of a coloring principle is required, such as madder for example. And a pigment cannot be regarded as a resin for making varnish, unless it is properly formulated as a rosinate for that precise purpose.

[Davide Sora]

15 hours ago, charliemaine said:

Can you explain how you incorporate the rosin into red madder when making a lake? 

The rosinates settle to the bottom of the jar when left to sit. Can this be scraped out of the jar and mulled into a varnish like a lake pigment? 

As Jackson says, that is, by previously dissolving the rosin in the alkaline solution where the coloring extract will then be added. When the alum is then added, a compound of resin + alum + dye will settle on the bottom of the jar.

Wash, filter, dry, grind, etc. like any other pigment

[charliemaine]

4 hours ago, Davide Sora said:

As Jackson says, that is, by previously dissolving the rosin in the alkaline solution where the coloring extract will then be added. When the alum is then added, a compound of resin + alum + dye will settle on the bottom of the jar.

Wash, filter, dry, grind, etc. like any other pigment

Sorry I didn't explain well.

Can I scrape and mull the rosinate(dregs) that settled to the bottom of the varnish jar? Shame to waste it.

 

[JacksonMaberry]

5 hours ago, Davide Sora said:

Yep, thanks for pointing out. In fact, not all rosinates can be effective as a pigment, the presence of a coloring principle is required, such as madder for example. And a pigment cannot be regarded as a resin for making varnish, unless it is properly formulated as a rosinate for that precise purpose.

Right, absolutely. The only exceptions might be copper rosinate (the oldest, as you pointed out) and iron rosinate, which have innate color. 

[JacksonMaberry]

1 hour ago, charliemaine said:

Sorry I didn't explain well.

Can I scrape and mull the rosinate(dregs) that settled to the bottom of the varnish jar? Shame to waste it.

 

Hm, odd. It might work sort of like tube paint, since it's already color-in-oil. 

[Davide Sora]

4 hours ago, charliemaine said:

Sorry I didn't explain well.

Can I scrape and mull the rosinate(dregs) that settled to the bottom of the varnish jar? Shame to waste it.

I honestly don't know, the presence of oil could make it too soft to be finely ground like a pigment. But if your waste varnish really got super hard and brittle, you might give it a try. Maybe we discover the still unknown way to color the varnish that Stradivari used, and start a new trend.

[sospiri]

2 hours ago, Davide Sora said:

 Maybe we discover the still unknown way to color the varnish that Stradivari used, and start a new trend.

Do all varnishes darken after 100 years?

 

[Davide Sora]

50 minutes ago, sospiri said:

Do all varnishes darken after 100 years?

 

I don't know if all varnishes darken over time, I suppose most do but probably others might lighten as well. Certainly some varnishes colored with pigments or fleeting dyes will lighten, a compound of linseed oil and rosin with no added colors I suppose will certainly darken by oxidation. But getting dark is one thing, turning red is another.

[sospiri]

On 5/20/2022 at 10:07 PM, Davide Sora said:

I don't know if all varnishes darken over time, I suppose most do but probably others might lighten as well. Certainly some varnishes colored with pigments or fleeting dyes will lighten, a compound of linseed oil and rosin with no added colors I suppose will certainly darken by oxidation. But getting dark is one thing, turning red is another.

I suppose everyone develops their own technique and it will still be identifiable long after they have passed. 

[Michael_Molnar]

Attention history enthusiasts: I found tucked in my Michelman book a letter from Michelman to the owner of my copy. If you are interested in history about his company:

Michelman Chemicals, Inc.

6316 Wiehe Rd.

Cincinnati, Ohio

You can see his building on Google Maps Street View.

 

 

[JacksonMaberry]

19 minutes ago, Michael_Molnar said:

Attention history enthusiasts: I found tucked in my Michelman book a letter from Michelman to the owner of my copy. If you are interested in history about his company:

Michelman Chemicals, Inc.

6316 Wiehe Rd.

Cincinnati, Ohio

You can see his building on Google Maps Street View.

 

 

That is way cool, Mike! I had the good fortune to exchange some letters with his son, John, who was also a chemist and led the company for many years. I believe Joseph's grandson is now at the helm.

[charliemaine]

Two blended varnish samples not as red but more durable.

[JacksonMaberry]

Nice! Glad it's working out.