Oil mediums
The drying time of oil colours
All Schmincke oil colours can generally be applied directly to appropriately prepared supports in coats that are not too thick.
Oil colours dry chemically by absorbing oxygen from the air. Moreover, sunlight plays an important role in this process. Drying takes a very long time and begins on the surface of the picture. For this reason, it can take weeks for even a relatively thin coat of oil colour to become completely dry.
ATTENTION: If coats of paint are too thick, this may cause tensions inside the layer of paint during the drying process. These tensions frequently lead to cracks or wrinkles. For this reason, we recommend the use of megilp (50034) when working with oil colours in a pasty form.
When a picture consists of several thin coats of paint, the bottom coats must be completely dry before other follow. For this reason, the traditional rule of oil painting applies “Fat over lean”. “Lean” paints contain less oil and, therefore, dry faster; “fat” paints contain a lot of oil and dry more slowly. The oil content of the paints can be modified by adding suitable oil mediums (e.g. MUSSINI medium 1 - 50038, MUSSINI medium 2 - 50039 or MUSSINI medium 3 - 50040).
Moreover, mediums can be used to influence numerous other characteristics of oil colours individually like, for example, consistency (medium N - 50045), flow (medium L - 50042), gloss (siccative de Harlem (50022)) and transparency (transparent paint medium - 50053, transparent gel -50037).
Some of the products listed in this section modify several of these factors at the same time (see table 2 for an overview).
To obtain certain product characteristics, we recommend that you use only one medium per coat of paint. Even if, from a chemical point of view, many mediums can generally be used together without problem, another combination normally makes no sense from the point of view of painting technique.
ATTENTION: To facilitate the complex drying process for oil colours and minimise their typical dark yellowing effect, we recommend that you do not store oil paintings away from light, especially during the initial stages. Suitable products for finishing treatment are listed here. Please note that oil paintings should be varnished only after all coats of paint have dried – after 8 to 12 months at the earliest! You will find suitable solvents, thinners and cleaning agents for oil colours and oil mediums here.
(Note: All oil mediums are ready to use and, if necessary, can be thinned down using turpentine substitute - 50019.) Those wishing to make their own oil colours and mediums will find detailed information on suitable binders and resins - here.
HINT: Oil colours, oil mediums and the associated solvents, thinners and cleaning agents may not be allowed to escape into the groundwater. Please ensure the proper disposal of any remains as hazardous waste. Please refer to the individual Safety Data Sheets for advice on safe handling.
