Please see recent oily rags discussion on the necessary steps to ignite linseed oil and how it largely does not apply to our handling of oils in painting. Tubes of oil paint and jars of oil do not auto ignite.

As for best cleaning method using oil, I have a video of how I do that on YouTube. I find using walnut oil works for me, but you can use a variety of oils. In fact, if you are using it solely for cleaning a brush at the end, the oil doesn’t even need to be a drying oil… you could use mineral oil or olive oil… whatever is cheap, and be sure to thoroughly wash the brush out with soap after. I actually just use my method in the video, and store the rinsed brush bristles suspended in oil with clips. I have had one brush in the jar for 4 years, and while worn down and the ferrule is chipped from scraping paint off the sides with my palette knife, it still works wonderfully for me in general use.

Choice of palette is really up to you, plexiglass however sometimes doesn’t clean up as easily as actual glass. Even cheaper is a piece of polished porcelain tile that you can get from the home improvement store for like 3 dollars. I have let paint dry on the palette and scraped it off with a glass cleaning razor blade I bought for $2 while I was there (it came with 6 replacement blades). You have lots of options with palettes and methods of cleaning them up.

Most linseed oils dry way too fast for me to use for brush cleaning. It also dries up in the glass jar, even with the lid on. I prefer walnut oil for two reasons:

1 – Slower drying
2 – If I inadvertently leave too much in my brush when cleaning it won’t cause my paints to take months to dry like what CAN happen with some grocery store non drying oils.

Don’t leave any drying oil, including walnut, in your brushes for too long or you will end up with a gummy mess. Even non drying oils can gum up over time if left in your bristles. Just wipe them off and re-dip them every few days to keep them wet, or if you prefer, wash the oil out when done, with soap and water or your favorite water based brush cleaner.

The trick to conserving leftover paint is to cover it (box with lid, plastic wrap over palette), and stick it in the freezer. It can’t oxidize at low temperatures, and a few minutes after you take it out, you can go back to work.

You can do this with brushes too, wipe the excess paint on a rag, and put them in cold storage. Just avoid letting any moisture get in (oil&water), and wipe them on a rag before painting again.

When you do clean your brushes, warm water and regular blue Dawn is all you need. Too many other cleaners will dissolve the glue keeping the bristles attached (OMS). You can also try the method of suspending your brushes in regular old vegetable oil, essentially never letting them dry as long as they live. I’ve heard of but never tried it.