Liquin + titanium white to make a type of magic white.
I use this on the last painting I posted to this group. My hopes were that I could use the wet on wet technique, but still have a painting that would dry within a day or two. One day later it is already dry to the touch except for the thickest paint layers, which are just slightly tacky. Has anyone else ever heard of someone trying this? Results? Ideas about this technique?
Sure.. lean on fat methodology. If I remember right, Magic White is just Ti white and linseed oil or maybe safflower oil.. the different oils add a different hue to the paint. Linseed adds a bit of yellow while safflower is pretty neutral. I'm told poppyseed is the best cleanest neutral oil but I've never tried it.
You can make your own mediums for this. It's quite a thing 
. I use linseed oil, turpentine and stand oil. I've also been working with Spike Lavender oil which is just an essential oil renamed. Its a solvent like turpintine but not toxic and smells much better 
. It is much more expensive.
Here is a. lot of details and opinions .. mediums have been made since ancient times and as you can imagine, there are a lot of opinions as to which is the "best". Personally I keep it simple.. I use stand oil and linseed oil 1:1 for "normal" medium.. gum turpentine and stand oil 2:1 for lean.. linseed oil and stand oil 2:1 for fat. I have some bottles with dropper caps so I can just puddle a small amount on my palette without any fuss. Some folks use Damar varnish in the medium.. I use that for glazing and it's fast to dry.. almost too fast but glazing doesn't take very long to apply and you don't want it melting layers below so it works well for that.
This site is a great resource overall and this thread is dedicated to mediums
https://www.wetcanvas.com/forums/topic/oil-paint-mediums-recipes/
I should add that stand oil is linseed oil that has been heated to start the polymerization process ( drying) so it dries much faster than normal linseed oil. You can see some folks say "sun activated" linseed oil.. leave it out in the sun for a while does the same thing without the heat. I'm not that much of a purest for my linseed oil
