How does solvent-free walnut alkyd medium dry?

[sidbledsoe]

Originally Posted by karenlee

Does cobalt drier cause what you refer to as yellowing? My bottles of M. Graham Alkyd walnut oil and Grumbacher MAX alkyd llinseed oil both display exactly the same color shifts---they both turn brown during storage. Really brown. I guess this would appear as 'yellowing' in a thin paint film. I hate to use such darkened oil in any paint tints.

I believe all types of driers can cause yellowing, here is a response from Amien that basically says don't even use them.

Cobalt driers are oxidation catalysts, drying the film from the top down -- this is not the way drying oils normally dry. Excessive amounts of drier can cause the paint films to wrinkle and yellow...We therefore do not recommend the use of these kinds of accelerating driers in oil paints.