Drying medium?
 

Do any of you use a medium that will accellerate the drying of your paint?

I'd prefer a tried and true medium that has been used for generations, rather than a new invention, since those make me nervous when it comes to their archival characteristics.

Any suggestions?

Michelle,

When I have to, I use a few drops of cobalt drier in my painting medium (which is 50-50 linseed oil-turpentine). It does not have a darkening effect on the painting unlike lead driers. I

Michele, precisely what sort of "problem" are you hoping to solve?
Siccatives are invariably linoleate metal salts. While they can accelerate drying time, they can't properly be considered "mediums".

Do you paint in a layered technique?

Do you employ titanium white and cadmium colors?

Carlos, cobalt and manganese siccatives have been around for about 150 years. Referring to lead driers as "darkening" piques my curiosity. If you are referring to lead naphthenate, it's a relatively new siccative, and I'm unaware of any darkening that is inherent with its use. Cobalt driers have been blamed for darkening paintings since their inception, however.

It's a fool's errand to cast blame on materials which cannot be identified specifically for their content and quality, and even moreso to condemn materials generically without full knowledge of the techniques for use which were employed.

There is not one single thing we paint with (or on) which cannot be misused to the point of causing failure.

I don't paint in a layered technique and I do use Titanium white. When I work with flake white it feels like I'm painting with skim milk.

The biggest issue I have is with black areas that seem to take forever to dry, especially with official portraits (in which the subject is often wearing a black suit) that often have firm deadlines.

Michele,
I also have to use Titanium White since lead is out of the marked here.
I always add some dryer to my medium ( I consider a medium being a mix of oil, turps and dryer )
I don't think that the small amounts of metal salts: lead, cobalt or manganese, that is required to accelerate the drying will affect the color, or cause darkening / yellowing of the paint.

The problem, as I have experienced it, is that we want the dark colors to stay transparent and therefore add more oil if the oil "sink" and leave the surface matte.
If the drying process is too slow then the oil will keep on sinking and we will keep on oiling out with the result of darkening the colors because of too much oil on the surface.
In other words it is the oil and not the pigment that causes darkening.

Over time the paint will get more transparent, so all supports should be primed in white. That would balance the expected darkening of the oils.
The white priming will do the job whatever or not we begin the painting with a wash of darker paint or not.

As with any other pigment, there are a lot of variations with differing pigment loads. Vasari flake is very good. Robert Doak offers a number of variations, SP is also very high quality. Naturally, flake is more transparent, while titanium is as opaque as one can find. Lead whites dry more rapidly, titanium is exceedingly slow.

Carbon blacks absorb much more oil than almost any other pigment. They also tend to be slow driers. Prussian blue and the umbers naturally contain manganese compounds, and dry rapidly. Mixes of the two can provide a rapid drying "black" that's almost as dark as carbon blacks from the tube.

If you haven't yet, try copal medium, I've had luck with Grumbacher; but I'm not familiar with other brands to know if they're similar. Speeds drying, but not as fast as Liquin.

Last time I examined a bottle of Grumbacher "copal medium", alkyd resin was the active ingredient. No copal was harmed in the making of this product.

Liquin and other alkyd preparations do hasten the drying rate of oil paint. Delamination can be a consequence of using alkyd mediums in layered techniques, however.

Opting for resin mediums (copals, balsams, damar, mastic etc.) the unique handling character imparted to paint by each of these is more of a consideration than drying time alone.

Richard, thanks for setting me straight on the imitation copal.

My pleasure, George. I hope to offend no one, it seems passions can run high when mediums and painting additives are discussed. There is more mis-information at large than truth, and the whole subject is a minefield for painters.

Add to this the fact that many high-quality standby materials (those " . . . tried and true . . . used for generations . . . " Michele requested) have been out of use by mainstream art materials suppliers for some time, and are becoming ever more scarce and difficult to obtain.

Examples: linseed oil has been supplanted by safflower oil as the vehicle in most tube paint, not because it results in superior paint, but because it is inexpensive, and readily available in vast quantities as its main application is in the fast food industry.

Pure gum spirits of turpentine is practically impossible to obtain, where at one time it was a common hardware-store or paint store item. The currently available foul-smelling stuff is steam distilled from stumps and forest waste, rather than fractionally distilled from pure sap tapped from living conifers. There is a world of difference in quality.

The natural and fossil resins have been supplanted by petrochemicals such as alkyds in the production of commercial paints and varnishes. Again, availability and low cost is the driving force behind their introduction into art materials, supplanting traditional resins such as copal, damar, venice turps, balsam, mastic etc., etc.

With a track-record of 500+ years of durably provable techniques, it seems to me there is little reason to re-invent the process of oil painting by employing synthetics and different materials that lack this provenance.