walnut oil / linseed oil - grassa

[Salamander]

This is from another forum and I would like to knkow what you all have to say.


"I wonder if there is a difference in the yellowing or strength and longevity of walnut oil when combined with egg yolk as compared to linseed oil used straight as a paint vehicle. Does the combination produce an even stronger and better medium?

Does walnut oil , when combined with egg yolk become a better medium than when used straight?

Walnut oil seems, from all that is said, is inferior to linseed oil. However walnut oil also seems to 'fit' better with egg yolk, (to me), than linseed oil. Less sticky. For example: yolk, walnut oil and dammar varnish behaves beautifully as a medium where yolk, black oil and mastic is a bit stickier. The black oil /mastic mix also dries to a flat matte finish where the et/walnut/dammar combination dries to a nice satin matte.

I wonder if the combination of egg and walnut oil is a better one than egg yolk mixed with linseed oil. Or even black oil for that matter. I like the idea of adding black oil to the tempera (mostly for bug proofing) and would like to get the lead in there some how. Is that futile? (In the past, when I have added lead naphthanate, it tended to cause the yolk to 'curdle')."

Any thoughts on this?
Thanks,
Eric in Oceanside

[sabine]

I dunno :-)

I use poppy oil, which works just fine and has the reputation to yellow very little (and a variety of other things: spike lavender, venice turpentine and damar varnish are the ingredients of my up-to-date recipe... still haven't tried cherry gum) and avoid lead as much as I can...

sorry that doesn't help you!

[Alessandra Kelley]

The tradeoff in all drying oils is yellowing versus flexibility: the oils that yellow the least dry to the most weak and brittle films (which of course crack and flake much more than flexible films). This cracking can be seen in thick areas of white oil paint in twentieth-century paintings, where the whites are often to this day ground with whiter (more brittle) oils to avoid the yellow cast.

Walnut oil is at the opposite end of drying oils. It dries to a very flexible, tough, strong film, but also darkens very seriously, past yellow and even to a deep brown.

Salamander, if I remember right, "black oil" is linseed oil which has been treated with lead to make it more flexible. This property is why lead paint was so popular for so long, but it also makes it a hazardous substance to handle.

[Salamander]

Black oil is hazardous if you eat it. Some pigments, especially those in dry form, are probably more of a risk.

[jeff]

I have made and used sun dried sunflower oil in the past and it seems to be a reasonably clear oil to use. It is better to use these sun dried oils for tempera I think since they have less shrinkage and dry faster. As for its flexiblity I can't say that it's better or worse than linseed oil though.