Drying medium?

[David Carroll]

Hi Michelle,

Garrett's copal heavey medium works well for accelerating drying. I've used it and like it. It Creates a beutiful shiny paint layer. If you call, Ron will talk with you about how to best use his products, and answer any questions you have. he's a very nice man. He will also probably send you a test sample if you asked for one. His copal products are very highly regarded.

http://www.garrettcopal.com/prod_hist.htm

The umber and p/b sounds real good too, especially if you don't want to add medium into your process. Sometimes I add a little OH titanium white (doesn't contain zinc white) into flake to make it more opaque. It sort of splits the difference.

Studioproducts.com sells High Quality mediums and materials and provides a forum with loads of info.

The more mediums I try the more I like to just paint with paint. It seems the only real concensus I've seen regarding the achival quality of oil paint is that anything added to the paint reduces it's archival permanance. Maybe Richard can share his knowladge on this point as this is just what I have read.

I hope this helped a little.

Peace,

[Richard Monro]

Michelle,

It is important to get some authoritaive advice on this subject in as much as most of what has been offered so far, while well intentioned, is opinion.

I suggest Ralph Mayer's "The Artist's handbook of Materials and Techniques" be referenced to find your answer. It is authorative, technically sound and thoroughly researched. Every artist should have a copy in their studio.

For instance, copal is a varnish not a drying medium, and copal has its own special archival concerns. Mayer's research will set matters straight for you.

[Richard Bingham]

Originally Posted by Richard Monro

. . . most of what has been offered so far, while well intentioned, is opinion . . .

Unfortunately, when advice on paint additives is requested, all answers are opinions regardless what facts, inaccuracies or good intentions entail. Definitive answers require the individual painter to acquire adequate knowledge through study, experience and testing to make pragmatic decisions as to which materials are compatible with his/her art.

Mayer's compendium is useful. It is not the final arbiter of questions about mediums and paint additives. His blanket condemnation of copal mediums in particular requires background. I am disposed to accept a wider viewpoint; I studied with Frederick Taubes, and grew up reading "Studio Secrets" and his Q/A tech page in "American Artist" long before Ralph Mayer held forth in that publication.

Taubes' technical knowledge resulted from extensive analysis and testing throughout a lifetime of concentrated study and interest in painting materials and methods. He favored the use of copal, and made varnishes and mediums of exceptional quality at a time when finer grades of Congo Copal were available. These were marketed through Permanent Pigments (now Liquitex). Apparently personal rancor existed between Mssrs. Taubes and Mayer, whose motives for condemning copal and its use may have been inspired by a desire to rankle Mr. Taubes rather than from strictly objective analyses. Consequently, certain of Mr. Mayer's pronouncements also qualify as opinion.

[Michele Rushworth]

I have heard second hand that a nationally known portrait artist uses Gamblin's Galkyd. Any thoughts on that?

[Richard Bingham]

Thoughts I have pertain only to alkyd materials, not who uses them. I have known a number of artists with national reputations whose work is superlative, whose materials choices and application methods I sometimes find worrisome from my own experience. It's tough to abuse either to the point of failure in a very short time, however, and after all, it's what the work looks like that interests the patron, not how, or with what.

Alkyd resin is a synthetic material derived from the combination of an acid and alcohol. The initial nomenclature reflected this, "al-cid" and later became "alkyd". The discovery was first applied to automotive utility coatings in the mid-1930's (DuPont's DuLux). Fast drying, tougher than nitrocellulose lacquer used well into the 1950's, it remains a staple for commercial and utility applications.

Used to advantage in oil painting where the work is completed wet-in-wet in one sitting, it should pose no particular problems. An alkyd medium mixed in colors, then subsequently over-painted stands a possibility of de-laminating. The addition of drying oils to alkyd vehicles makes fresh applications painted over dry films especially prone to separation unless the dry layer is abraded to provide a mechanical "key" for bonding (i.e., "sand between coats"). This is because surface-dry layers of alkyd paints do not fuse with fresh paint through solvent transfers and resulting chemical bonds as natural resins permit.

Again, why "mess" with a system that (with all its possibilities and complexities) has worked for 500 years? It will require another 100 years to find out if alkyds are better or worse than anything that has been used in previous centuries.

[Michele Rushworth]

Everything I've read (both here and elsewhere) makes me think I'm still better off just continuing to use paint straight from the tube, as I have been for the past several years.

A different nationally known artist told me he accellerates the drying of his paintings by using a space heater and a fan. Seems safer than a lot of the different mediums and additives that are out there!

[David Carroll]

Originally Posted by Richard Monro

Michelle,

For instance, copal is a varnish not a drying medium, and copal has its own special archival concerns. Mayer's research will set matters straight for you.

True, but I suggested this medium as an example of a medium that has been around for generations, and also speeds drying. Ron is second generation maker of this stuff and I believe that it is made from the recipe and production process that Taubes employed and passed down to his students. There is however the difference of a less hard copal available today as compared to the original. In my experience it will accelerate drying, usually I can over paint in a day or two. But I live in the southwest and everything drys faster here, plus I usually use a lead white. Also of note on this stuff, It is a cooked combo of copal resin, stand oil, and turpentine. If you are sensitive to turps you will want to avoid it.

Just my opinion

Peace,

[Richard Bingham]

Originally Posted by Michele Rushworth

. . . think I'm still better off just continuing to use paint straight from the tube . . . accelerate drying . . . by using a space heater and a fan. Seems safer than a lot of the different mediums and additives that are out there!

So long as your paint is high quality, there's no question that's a sound approach. Paint definitely dries faster when it's warm and dry, and air movement speeds up the process, so controlling the studio environment to hasten drying time is certainly an option.

The biggest problem for those who buy mediums is assuring the quality and contents of "store-bought" mediums. (e.g. the "imitation" copal medium mentioned above) As far as "safety", we tend to do a lot of hand-wringing over "archival permanence", but the truth is that it's really, really hard to force painting materials and mediums into failure. Even the worst materials and practices generally have to age 50 to 80 years to become visibly obvious.

Speaking of copal, the term is as non-specific as saying "use apples". There are a number of resins collected commercially from Mexico, Central America, Africa and Indonesia all identified as "copal" although different species have quite different characteristics. Congo copal was the standard for clarity and hardness in the days when natural resins were used to manufacture the bulk of varnishes used for home and commercial finishes. Owing to the on-going political strife in that region of Africa, it hasn't been commercially available for many years.