How do you slow the drying of thick impasto oil paint (stand oil added as medium) to allow it to be worked for several days? I know pigment selection is crucial, as well as temperature/light exposure. Maybe spike oil substituted for odourless solvent, a less absorbent acrylic ground, may help. Poppy oil does help but the dried paint film is more brittle (from testing of samples). Am I asking the impossible to extend the drying time of fast driers like cobalt blue and also for it to remain flexible. I even had a box made to store the painting overnight with cotton balls soaked with clove oil, but this puts size restraints on the painting size. I seem to solve one issue to just raise another one. Any thoughts would be appreciated.
Thank you for the answers to slowing the drying rate. I have noticed quite a variability in the drying rates of several brands of the same pigment. I will do further testing of different paint manufacturers to find those with less dryers added. A very good suggestion.
My first suggestion is to use oil paints that contain no added driers. Almost all commercial oil paints have added multi-metal-salt complex driers used to facilitate a plethora of issues but also to create an oil paint line that dries in a “similar” time frame.
Making your own oil paint (which will inevitably be more fatty and coarser in texture than paint made on a three-roller mill) would likely surmount your issues. However, so would seeking out a commercial oil paint with NO thickeners/stabilizers, and more importantly, NO added driers. This would require far less effort and would likely result in a more satisfactory painting experience than making your own paint.
You can make great paint on your own, but it will take a huge effort and will almost always contain more oil than that made using a three-roller mill.
Despite all of the above, I will always have a supply of hand ground lead white (stack lead white if I can afford it) in an acidic linseed oil on hand for specific effects. It is unnecessary for many things, but essential for others… required by me, but by no means required to make quality paintings…but just my kind of paintings
If you are resorting to radical prceedures like spike oil-soaked cotton balls, you may need to rethink the basic premises. See my above post.
This reminds me of the severe steps taken to get around the suede-like effects seen in 20th century oil paints. Taubes suggested adding large amounts of stand oil/copal-stand oil to get around this gremlin. It was really just a result of the use of large amounts of aluminum stearate or hydrate (or even beeswax) as a stabilizer in 20th century commercially prepared oil paints. It is amusing to read the early literature suggesting that this defect was a result of using alkali refined linseed oil vs cold pressed oil and not the effects of aluminum salts/ etc.
