Artist oil paint additives

[nolan]

don't delete the post, just modify it 

[Leana]

Steven, I thought you might have left it out on purpose  ...that you perhaps preferred it without the VT  ...so I was uncertain     How are you enjoying the mix without the Venice Turps though 


The freezer trick really works well to keep paint 'fresh'

[Steven]

Nolan, since Leana did such a nice job of saying what I thought I was saying it made my post redundant, next time I'll modify though so follow on posts have continuity.

I was a bit embarrassed to say Leana    since in my unfamiliarity with the difference between Venice Turpentine and spirits of gum turpentine I actually substituted the gum for the VT    heh, it did say artist's spirit of gum turpentine on the label so I thought it was just a brand thing and not a completely different animal!  After your post I looked up the two and saw that indeed the VT is not a solvent at all...

So, I can't report on how the mix works sans VT, but I can say it worked, as you might suspect, a little too well with the spirit of gum turp.  The paint does stay wet much longer, I like having all my paints more or less the same consistency and it's just a bonus that the clove oil and piney smell from the spirit of gum turp actually make the mix smell nice!

Two of my paints didn't work well with the mix though, the burnt umber started out fine but started drying in the jar after a couple months.  The other bad actor was my cadmium orange... it was really runny and i suspect the turpentine might have been the culprit  I wasn't able to find the Venice turpentine locally so I have no comparison to what the actual mix is supposed to be like.  Will let you know when I find some.

Oh, and I was using part of my wine refrigerator for keeping my paints fresh through the summer.  The more I drank the more I thought about getting back to painting 

[Leana]

Steven, no need to feel embarrassed whatsoever  ... this is how we all learn...by sharing information  and this is the best place for it.  There are tons of artists that think Venice Turpentine is a solvent...I think because of the word 'turpentine' in it. 

Burnt umber is a faster drying colour that's why Mark adds additional Oil of Cloves to the jar of the Burnt Umber.  Also the Cad. Yellow will need a little less medium, because it becomes much 'runnier' than the other colours and this is visible only the next day. Something to do with the Cadmiums and the medium...that is also most probably why your Cadmium orange was runny. 

The Italian paint manufacturer 'Maimeri' has a Trementina Veneta (Venetian Turpentine...which I believe is the same as Venice Turpentine...just names slightly different), maybe some of the art shops in your area will stock Maimeri...

Just in case you don't know...the Odorless Mineral Spirits dries slower (or rather evaporates slower) than Gum/Mineral Turpentine...that is also why it is used in that medium.

The overall mix of the Slow Drying Medium will be slightly thicker/viscous due to the Stand Oil and Venice Turpentine present compared to the use of Gum Turpentine in the mixture.

Wine refrigerator  great place for storing your paints...

[thebryce]

So what additives do I use for a background wash? I see that some painters just put down acrilic and then after it drys they cover it with linseed oil and paint  wet on wet.   I assume a wash of a more blenable oily paint mix would be acceptable too for backgrounds, right? I am not sure what thinner to use that would allow for that kind of wash and not eat at the paint stability in the future.

[scouserl41]

Bryce,
Depends on what stage of the painting you are at. Generally I start with a watercolor pencil to lay out the basics on the board/canvas then I will do an underpainting to try basic colors and tonal levels. This could either be acrylic (Nice and opaque dries real fast) or oil paint in a neutral color thinned with terpentine to put in the outlines and darker areas. That is very thin and dries fast. Another approach is the neutral color thinned with oil medium which also dries fast, you can add colors to block in the basic painting.
Doing it lets me see how it sits on the board without using tons of paint, when I'm happy then I can lay on the thicker paint to finish the picture.
I paint the background first in the final go around and generally let it dry before putting in the foreground.
Remember you can paint oil over acrylic but NOT acrylic over oil.
Brian

[thebryce]

Is there a difference between paint thinned with terpentine, or linseed oil or a mineral spirit of some sort?

[scouserl41]

I'm not an expert nor did I play one on TV!
I was told at my local class not to use terpentine for thinning oils as a normal practice because ir's a solvent (as are the other 2 you mention) and in time can break down the paint and lead to flaking.
Commercial paint mediums will "thin" the paint but not damage the paint.
I've stuck to that, I have no evidence to contradict it so unless I get some I'll keep going that way,
Brian

[Germa]

Is there a difference between paint thinned with terpentine, or linseed oil or a mineral spirit of some sort?

There's a big difference, terps make your paint more lean, oils make your paint more fat.

I never use any medium, but linseed oil or a fast drying 'ready bought' medium which makes the paint more fat. And I just use them, when my paint is a bit too thick.

[nolan]

never use turps to thin your paint, only oil or a reputable brand of painting medium. You get "thin" painting mediums which especially designed to do the background washes you have in mind 

[thebryce]

I tried my 1st oil painting last night. It was a disaster. Oil paint everywhere. I tried liquin original and then the impasto. Then tips to wash off the mess.  Nothing looked right. The mediums were wierd. Perhaps I did not need them but I wanted fast dry. Nothing dry yet. How long does impasto take?

[Germa]

That depends on the weather, the humidity and how thick your layer of paint is. I painted very thick flowers with the knife, the paint + impasto were touch dry within a week. (think of a half cm. thick layer of paint).

[nolan]

  oil paint takes long to dry - with a drying medium added, it can still take days