Tip: Glazing Mediums

In anticipation of Jeff Hepworth's upcoming class I tried to find the ideal glazing medium. Up to this point I had been making my own glaze using the most simple of recipes:

1 Part turpentine (or mineral spirits)
1 Part oil (linseed or walnut)

While this has worked well for me in the past, I have wondered about using commercially available mediums (such as, Liquin and Galkyd). Although these products are more expensive, the overall cost is minimal when you consider the amounts used in painting.

It appears that most commercial products are made from alkyd. Alkyd is a syn­thetic resin that speeds the drying time of oil paint. It also increases the flow and transparency of the paint it's mixed with. Thin layers of paint mixed with an alkyd medium dry in less than 24 hours. According to the manufacturers you can add up to 50% by volume mineral spirits (or turpentine) to reduce the viscosity of alkyd mediums when they are to be used in glazing.

I know many artists that use these commercial mediums but there are others that express concerns about using these products, especially for glazing. Here are the concerns:

• There are a few reports of poor adhesion between layers of paint con­tain­ing alkyd medium. This could be a problem when glazing the same area multiple times.
• Alkyd medi­ums can yel­low­. This is not a problem when the medium is only used as a thinner, but it is more of a concern when glazing.
• Since alkyd mediums dry quickly, they can damage your brushes unless the brushes are cleaned immediately after use.

After hearing the concerns, I wondered what other options there were for oil glazes. Here are a few more homemade alternatives I found. The first is also very simple.

4 Parts stand oil
6 Parts mineral spirits (or turpentine)
(from several authors, WikiHow)

According to this author the medium dries in a moderate amount of time, contributes a moderate gloss to the paint film, sets up stiffly when glazed thinly but allows some degree of over painting while still wet, and yellows less than linseed oil mediums.

1 Part stand oil
1 Part damar varnish
5 Parts turpentine
(from Utrecht)

This recipe is offered as an all-purpose "lean" medium for painting and glazing. This means that when adding multiple layers of glaze, additional oil will need to be added to this recipe to comply with the "fat over lean" rule.

The next two recipes come from Jodi Brody. The first is very similar to the one just provided.

1 Part linseed oil (sun thickened)
1 Part damar varnish
2 Parts turpentine
Lavender oil - 3 drops per 1 oz (add just before using)

Jodi explains that this medium is similar to the ones made and used by the Masters. It will give you good control when glazing.

9 Parts damar varnish
9 Parts turpentine
4 Parts stand oil
2 Parts Venice turpentine
(From Jodi Brody, WetCanvas)

Jodi calls this one a Venetian Glazing Medium and indicates that it is one of her favorites. This recipe gives a glossy finish to the paint and produces a stained glass appearance, with beautiful diffused highlights.

Here is the most unusual recipe I found. It comes from an undisclosed source but the author speaks very highly of it. It sounds like a homemade alternative to alkyd mediums.

1 Part linseed oil
1 Part mineral spirit
1 Part PENETROL (a paint conditioner sold at Home Depot)

The author says the conditioner fills the role of stand oil and makes the paint dry hard and fast. Without adding a drier the paint will be dry to the touch overnight.

While there are many other alternatives out there they all seem to be variations on these basic themes. I guess the best thing to do is try one and see what you think. That is what I will do.

Regardless of which alternative you choose, you should only mix enough medium to last you six months. The mediums should be stored in glass jars that seal tightly with a lid. You should store the mediums in a cool dry place when they are not in use.

Happy glazing...