|
Hard pressed to know about linseed oil?
Erica,
"Cold pressed" designates that the linseed oil has been created by pressing the flax seeds and expressing the oil. CP is prone to yellowing which can be reversed through exposure to daylight.
If the CP oil is then heated in a vacuum it becomes polmerized and is called stand oil. It is slower drying than CP, doesn't yellow, makes a flexible paint film, flattens the paint and reduces "sinking in." It is very fat. SO and CP have a great track records.
If the CP oil is further pressed it is called refined, although there are numerous other ways "refined" is processed. It dries slower than CP and faster than SO. It is less yellowing than CP but due to the additional processing and the resulting oxidation it forms a weaker paint film.
I use very little stand oil, in my initial layers since it can eventually create a beading up of paint in the upper layers. Therefore I add more stand as I near completion.
I use many brushes while I paint, one for each value of each color. I don't constantly dip in solvent or oil to clean them as I paint. I believe this muddies the colors and degrades the paint film.
Since the alkyd resin begins to set up immediately I find that my brushes have a far too short lived existance. One of the many reasons I choose to avoid resins.
It is very important for artists to understand the properties of the materials at their disposal, so that the proper choices can be made.
Hope this all helps.
Linda,
The title's for you!
|