[MrSmith56]

I am an oil painter.
I have a process to make an oil medium (what you mix into oil paints to make them more pliable).
This process adds Manganese and makes the oil paint dry super fast (one to three days!)  The old masters used this method. This is a big deal for oil painters because the oil-paint drying time is phenomenal! Also, it is thought to be non-toxic. Many oil painting mediums are very toxic so this is  a huge bonus.

Here is the process:
1. Fill a mason jar with 1" water.
2. Add 7 tablets of manganese 10mg tablets (Manganese gluconate). This is a dietary supplement.
3. Add safflower oil (Lou Ann safflower oil is very light yellow, not dark)  to fill the jar until it is almost full.
4. Shake every day for 2 weeks. Leave top off for air. Let the sun cook it every day.
At this point the manganese stays pretty much in the water at the bottom of the mixture. It makes a white gunky material. When you shake the jar it turns the whole thing milky white for a while, then it separates back out.
5. After 2 weeks have passed, filter (using a coffee filter) and pour into an open glass bowl.
6. Let sun cook it every day.  Stir once a day.
7. After a week it is almost clear and can be used to mix with oil paints, which will dry super fast.

I think the safflower oil could be substituted with any type of vegetable oil. We use safflower oil because it turns almost clear after the sun bleaches it.  I am also assuming the step of placing it into a bowl is to help evaporate all the water out.
1. But what exactly is the process making?
2. Is there a way to speed up the process?

Any help appreciated!  Any ideas?

[SirRoderick]

Hard to say what it is the Mg is actually doing. Most Mg compounds are actually oxidants and I'm assuming that would be bad for paintings. I mean it's obviously reacting with something, but I don't think you can tell just like that.

As for speeding the process up, it's best if you prepare several samples and experiment with different degrees of applied heat. More heat means it dries faster, but it might deteriorate an active ingredient. Any source of heat would do as long as it's ventilated so it can evaporate. Obviously i don't think boiling it is a good idea, but lower heating could very well save you some time.

[Borek]

Hard to say what it is the Mg is actually doing. Most Mg compounds are actually oxidants

Mg?

[SirRoderick]

Hard to say what it is the Mg is actually doing. Most Mg compounds are actually oxidants

Mg?

Sigh, I always do that. Sorry.
Mn of course.

Somehow I always mix those two up. I swear It's just a slip of the mind, I know the table perfectly well.

[rjb]

MrSmith56,

I think SirRoderick is probably right, Mn is acting as an oxidiser. Alkyd paints, i.e. oil based paints normally cure via an oxidative process during which the unsaturated long chain fatty acids are able to crosslink. This is normally driven by atmospheric oxygen but I presume could be speeded up with the addition of an oxidising agent? I presume it would be possible to speed up the reaction further, but I wonder if it would really be all that desirable or produce a stable vehicle that lasted a lifetime or more...

R

[MrSmith56]

Thanks everyone for the replies.  I realize this is an old thread but I thought I'd post a final comment in case some oil painters came across this message.  I never did find a good way to create my quick drying clear oil painting medium in a timely way.  I tried speeding up the process with several mechanical methods but it didn't pan out. It is just a long tedious process. However, I did find a place that I could buy it ( www.abcoils.com ) and it looks far superior to what I was doing. I believe he uses not only manganese but some other dryers also. As long as it is clear and helps the oil paint dry faster then I am happy!

Cheers!
MrSmith56

[IsotopeBill]

This is interesting:  I like the idea of experimenting with different oxidizing agents.  Another this is trying different light sources - a trip to the local hydroponics shop (or online) will reveal a variety of high-intensity grow lamps, in the visible and UV range.  This whole thing would be a good senior project for an undergraduate science major.  If you live near a college or university, a few inquiries might be welcome

[curiouscat]

I'll play the skeptic here: Are we sure there's an effect? Have you tried just safflower oil? What are the differences in drying time.

Let's quantify the effect before we try to explain it.