Painting mediums

[Christine Lewis]

Hey everyone, I am a bit confused, or uncertain about using painting mediums.

I noticed Richard using some walnut oil, so I got some to try. I have read so many different things about medium, but most people talk about how it makes the paint dry faster. I am interested in making the paint flow, or be thinner like Richard thins his darks. I guess my concern is using too much or not knowing when to use paint thinner instead of oil medium. I hear people say to paint thick on thin or fat on lean ( I think).

I Know I am not worried about the longevity of my pictures at this point, but I would like to understand the principles behind using  these. I don't want to do something that will cause my paint not to dry, or to be runny.

Can anyone give me a few guidelines? Thank you ( =

[Ann Turner]

Nice discussion, I'll have to try some Galkyd lite to see if I like it.

[Christine Lewis]

That sounds great, Stu...I will have to try it! ( = Thank you

[Stuart J. Gourlay]

Good observation Christine.  Richard paints on oil primed canvas (I know, because I have one of his paintings); oil paints do flow better on oil primed canvas or linen, because they are less absorbent of the oil in the paint and it is the oil that lowers the viscosity and improves the flow of the paint.  You can also take your Gesso (universal) primed canvas and pre-coat it with a layer of alkyd resin; this would be the same as "oiling out" that you can read about on the Gamblin website.  In essence, what you do is take Galkyd or Galkyd lite and thin it about 50/50 with Gamsol (OMS).  You then brush it  over the whole panel, wait about 10 minutes and remove any excess with a paper towel.  This will be dry and ready to paint on in a day or two; you will find that your paint will flow better, with or without medium, on this surface than on the bare Gesso.   Stu

[Christine Lewis]

Really appreciate this discussion and feedback! I have read a little more, and think I will probably try the Gamblin Galkyd lite. For the most part I have not used any medium up until now, but like the way it seems to flow more when I watch Richard's videos. I wonder too, if it has something to do with the canvas he uses. I am just practicing on Gesso primed canvas boards right now, for the most part.

[Michael J. Severin]

Galkyd Lite is a medium that mimics the properties of the turpentine, Linseed Oil, and Damar formula ...but does not have the drawbacks that Stu talked about.  It is also very much less toxic ..not non -toxic,but very safe due to the low evaporation rate of the OMS. This medium is made by Gamblin.

[Stuart J. Gourlay]

I would be quite careful about "Ed's Medium" and here is why: Damar varnish is very minimally soluble is room temperature OMS and can precipitate out; this causes a "blooming effect" or white haze all over the painting.   I think the reason that this works at all and the Damar resin does not precipitate is that the Damar varnish used in it is Damar resin that has been solublized in turpentine (the label on the bottle of Winsor and Newton's Damar Varnish reads: "Damar resin/turpentine/alcohol based").  The problem with turpentine is that it is one of the most toxic substances used by oil painters (lead based paints would be more toxic) and one of the most likely to cause skin and respiratory allergys.   The reason that mineral spirits and odorless mineral spirits (OMS) are so widely used is because of this.  Although some artists still use these classical formulas, most avoid turpentine completely.  A great source of formulas for homemade mediums is Ralph Meyer's book "The Artist's Handbook of Materials and Techniques".  Here is a website that gives a nice condensed summary or oil painting materials in general: http://homepages.ius.edu/dclem/ptgguide/ptggd2.htm  .  I don't mean to criticize Ann in any way, because for several years I painted only with "Donna's medium" from my friend who got me back into oils from acrylics about 15 years ago.  Donna's medium was 1/3 turpentine, 1/3 cold pressed linseed oil, and 1/3 Damar varnish; nice medium for painting, very smelly and drove my wife crazy but fortunately never caused me any toxicity.  There are much better and safer mediums out there today.   Stu

[Christine Lewis]

thank you Michael and Stu for your input is greatly appreciated. I will go to the Gamblin website and research a little more thanks so much again!

[Stuart J. Gourlay]

Christine, there are many different mediums. Their most common use is to make paint flow better. They often contain oils (linseed oil and walnut oils are the most common). All oils slow drying and some more than others. Many mediums contain solvents ( turpentine and odorless mineral spirits are the most common). Another common ingredient is a natural (Copal, Damar) resin or varnish, or a synthetic resin (alkyd resin). Occasionally, minerals that accelerate the drying or polymerization of the drying oils that bind the pigment in the paint film (linseed oil, walnut oil, safflower oil) are present. The alkyd resins are very popular because they accelerate drying and increase gloss. Popular brands are Winsor-Newton's "Liquin" and Gamblin's "Galkyd". These come in liquid and gel forms. Richard uses walnut oil with an alkyd resin; I think it's made by Daniel Smith. A good source that explains the use of mediums is the Gamblin website: www.gamblincolors.com. I hope this helps. You can also get info on WetCanvas in their forums, plus I'm sure you will get some other answers. Your walnut oil medium, by itself, will slow drying and improve flow and increase gloss. If you don't mind the longer drying time, I think you'll find it makes it easier to apply the paint. Stu

[Michael J. Severin]

Hi Christine.  I would suggest that you go to Gamblin's website and read about their painting mediums and what they do.  If you use walnut oil, the painting will dry slow.  If you use linseed oil  or any of the alkyds, they will dry fast.   There are many, many, oil mediums ..too many to talk about here, but do research it.  You do not need a lot of medium when you are painting, and the ratio of medium to paint must be kept low!  Some artist do not even use medium.  The medium that you decide to use, will be the one that fits your painting style.  I would suggest for right now, use Gamblins Galkyd Lite.  It is like a traditional medium of linseed oil, damar, and turp., but is safer (less toxic) to use then the traditional medium.  Walnut oil is good also....try not to use medium in your lights ...use nice thick paint.  This is a humongous subject Christine ...research it and you will get all the answers.