http://www.naturalpigments.com/vb/ Rare and Historical Artists Colors and Materials en Thu, 17 May 2012 07:23:48 GMT vBulletin 60 http://www.naturalpigments.com/vb/images/misc/rss.png http://www.naturalpigments.com/vb/ http://www.naturalpigments.com/vb/showthread.php?3419-Galkyd-and-Walnut-Concoction-to-heat-or-not-to-heat&goto=newpost Thu, 17 May 2012 01:27:43 GMT (1 : 1 : .5) Graham Walnut Oil : Galkyd Lite : Gum Turp

After using this it seems as though I'm using straight walnut as far as drying time goes however I'm not entirely convinced the two substances are mixing together well enough. It just seems that some of the walnut oil inevitably sits on top of the Alkyd which has gasped for air through the walnut to dry itself before the walnut - it even feels like the walnut sits onto of something - and that would be the Galkyd lite.

Would cooking, heating, or boiling these together create a better bond or is this pointless ? The whole idea of this was increase flexibility of the walnut and drying speed and avoid Grahams own version which seems terrible in review. Maybe I don't have enough turps ? It just seems weird to me, of all the other mediums I have experimented with this one does not bond well. In review of this medium, aside from fluidity and yellowing factor I'm beginning to think walnut is inferior to linseed or even Gamblins Galkyd Lite frankly.

I plan on replacing my walnut oil (or at least trying NP sun thickened version in place) in all my mixes with a fast drying, fluid, minimal yellowing linseed type oil. I want to try NP black oil but is that enough on its own to get what I'm after? Is NP Epoxide good to mix with others like venice turp and stand oil? What is a good fast dry, low yellowing, fluid NP linseed type oil.

I've also been playing around with NP Damar and stand oil mixes but aside from the drying time of damar it just looks like the stuff on its own was born to crack in due time - its says "brittle" to me ? I'm also confused on using it with your medium then varnishing which you hear may pose problems when trying to clean varnish in 100 years and inevitably removing some of the painting with it. Does using a completely different "synthetic" type varnish detour this problem ? ]]> Materials and Techniques ntrentadue http://www.naturalpigments.com/vb/showthread.php?3419-Galkyd-and-Walnut-Concoction-to-heat-or-not-to-heat http://www.naturalpigments.com/vb/showthread.php?3418-Tempera-Grassa-atop-Oil&goto=newpost Tue, 15 May 2012 13:49:57 GMT On the subject of tempera grassa....There is a website devoted to Van Eyck's Ghent altarpiece:http://vaneyck.kikirpa.be/It allows for high magnification and you can get very close to the work. There have been writings about Van Eyck and others in the transitional period between egg tempera and oil which claim painters were using both oil and tempera, and/or tempera grassa - but it all seems rather fuzzy, how (or even if) they combined the different mediums. Looking at Adam in the Ghent altarpiece, his skin tones are smoothly blended (as they would be in oil) but on top of him sit innumerable, crispy rendered, fine hairs (very linear, as if done in tempera). As I was scrolling over Adam I came across (above the knee cap and below his fig leaf) hair lines that aren't crisp but instead have beaded up - i.e. like a water media applied atop oil. I'm presuming this is tempera or TG on top of oil? Any other thoughts on what would cause the paint to behave that way; or what mediums are in play here, in what order?Koo ]]> Materials and Techniques Koo Schadler http://www.naturalpigments.com/vb/showthread.php?3418-Tempera-Grassa-atop-Oil http://www.naturalpigments.com/vb/showthread.php?3417-Preparing-Earth-Pigments&goto=newpost Mon, 07 May 2012 23:41:56 GMT I imagine this question has been asked before, but I couldn't find the thread. Traveling in Mexico I found an exposed cliff wall full of earth pigments - purples, reds, yellows, greens. I've taken some home and played with them and they make beautiful paint. But I recognize that they should be processed before being used in an actual painting (i.e. to be archival). What are the various steps necessary to make an earth pigment suitable for painting? What are the drawbacks of working with pigments from the backyard that have not been washed, etc?

Koo ]]> Pigments Koo Schadler http://www.naturalpigments.com/vb/showthread.php?3417-Preparing-Earth-Pigments http://www.naturalpigments.com/vb/showthread.php?3416-Shellac-on-Tempera&goto=newpost Mon, 07 May 2012 23:26:31 GMT I glaze oil paint very thinly atop my tempera paintings, but before doing so I isolate the tempera with shellac. (If I don't, I find the absorbent true gesso ground and tempera painting suck up too much oil and the paint drags). I use only bleached varieties of shellac, mixed myself, in very thin formulations (a 1:12 shellac/denatured alcohol ratio). From what I've read about shellac, whatever percentage of yellow appears in it when initially mixed does not increase over time and my mix starts out virtually clear (and my 13 year old test strips have remained clear). I've read that it does become a bit brittle, but its going on top of a solid panel support. I have checked with conservators in the past and have been given their approval for this process, but nonetheless I run into painters who are surprised I use shellac in this way - they say shellac is too brittle, yellowing, and prone to cracking. So my questions are...

1. Does anyone have any thoughts on this process - its pros and cons?

2. Is it true that shellac does not increase in yellowing over time (i.e. is it photo stable? Is that the correct term?)

3. What percentage of shellac is needed to successfully isolate the tempera/true gesso ground? I find my 1:12 ratio works okay, but wouldn't mind applying a slightly heavier solution (maybe 1:10 or 1:8) to more fully isolate the tempera. How much shellac could I use and not experience too much brittleness, yellowing, etc...?

4. If the shellac is quite dilute (as in my ratios above) could I paint tempera grassa on top of the shellac? What is the ratio of shellac in india ink? (Since pure tempera can go over india ink, I'm presuming the slightly more powerfully binding tempera grassa would adhere to a full coating of shellac if the shellac were about the same ratio more or less as india ink).

Thanks!

Koo ]]> Materials and Techniques Koo Schadler http://www.naturalpigments.com/vb/showthread.php?3416-Shellac-on-Tempera