[johnyd]

From those of you that have used oil paints I have a couple of questions.

Thank You in advance for your replies.

- I am going to finish a painting in one day, and will be using a lot of thick oil paint. I read somewhere that it's good practice to place a thinner layer of oil first so that the paint later doesn't crack.

For instance if I paint thick first, and thinner coats later will the paint crack.

Also what do you use to clean your brushes, and do you clean a brush after every stroke?

What thinner do you suggest is best.

That's all. Thanks for the time.

[MadSamoan]

You could lay down a layer of linseed oil, but many alla prima artists initially work in thin mixtures of oil paint and then get thicker gradually. Thin coats of paint are easier to paint over or correct than thick paint that is still very wet. Alla prima doesn't mean that you're using thick paint, it means that you're applying paint on top of paint that hasn't dried yet.

You don't clean your brush after every stroke, just when you're going to use a different color on that brush. For this reason, keep multiple brushes of the same size.

Turpenoid is highly recommended or something similar like turpenoid natural or odorless mineral spirits. They're not as toxic or have the noxious fumes that turpentine does.

Also, don't throw your turpenoid out after each use. It's actually quite reusable, just let the pigment settle at the bottom and the pour the clear turpenoid into another container and wipe out the residue at the bottom.

[johnyd]

I know what alla prima means I didn't mean to make it sound like thats what it is.

here is the exact definition
Alla Prima - An oil painting can be completed all in one sitting using a technique called �alla prima�(Italian for �at the first�). This is sometimes called direct painting. With this technique the painter will start with broad general strokes to get the general form. This is usually done with thin paint. Usually the darks are brought up first. Next paint is applied directly over this wet paint in thicker, more opaque layers. It is very important to keep the colors clean and the strokes accurate and decisive. It is very easy to make a muddy mess. The actual variations on this style are limitless. It may not necessarily be done in one sitting. One of the great masters of this style was Peter Paul Rubens.

Thanks for all the answers, someone also mentioned that it turpentine can be used as a oil thinner while painting. Is this true? I am going to buy a special oil thinner, but would just like to know if that's correct.

Thanks

[MadSamoan]

You can use turpentine, but it's really highly toxic. If you're going to be in doors, turpentine is a bad idea. It's very noxious, especially if it has been sitting for any lengthy amount of time and will offend other people. It's very toxic and has led to health problems in artists, Frazetta himself attributed using a bad batch of turpentine in his poorly ventilated studio to contributing to his health problems. Many schools/institutions won't let artists use real turpentine in classes/workshops. Turpenoid is used alot nowadays and it pretty much does the same thing with virtually none of the potential problems of turpenoid.

[johnyd]

Thanks

[Lunatique]

The cracking is just the "fat over lean" rule. When you apply a layer of paint that dries quicker than the paint underneath it, it's going to crack. Just keep the slower drying mixtures/paint on top of quicker drying ones.

[ May 19, 2002: Message edited by: Lunatique ]

[Markus]

There might be some tips/info you can use here... http://www.digitallaprima.com/wkshp_oils.html

These are only suggestions and basic info,
remember, there are no rules... just tools.
I'm sure there is no shortage of differing opinions...

[pierre]

Hi johnyd

you said
"- I am going to finish a painting in one day, and will be using a lot of thick oil paint. I read somewhere that it's good practice to place a thinner layer of oil first so that the paint later doesn't crack.

For instance if I paint thick first, and thinner coats later will the paint crack.
"

If you are going to finish an oil painting in one day, you will pretty much be forced to paint ala prima, unless you want to use sickative in your oil paints, which I don't think you want, and would never recommend either.

Lunatique mentioned the "fat over thin" rule. It is as old as the hills and equally true.

I believe you want to use an underpainting of some sort, use thin acrylics for that (it will work with thick also depending on how glossy your acrylics are). The paint will stick because all acrylics have microscopic holes and structures to suck and grab the paint. Even though usig acrylic as an underpainting is not completely risk free, it very often provides an easy and better way for it than oils. Consider that most canvases today use acrylics based primer, like gesso; it is pretty much the same chemical compound as acrylics. Using acrylics will render your underpainting dry for overpainting with oils in virtually an hour or two (letting it dry thoroughly is good).

If you use oils for underpainting, make sure to isolate it with a middle varnish. The fatter your underpainting, the more motivated the middle varnish, but then again, keep your underpainting thin.

you said
"Also what do you use to clean your brushes, and do you clean a brush after every stroke? "

Use soap and water. Do not use strong thinners like turpentine based stuff. Your brushes have a natural fat layer or equivalent for synthetics that you destroy if using strong stuff. If you can't clean right away after painting, wipe your brushes of from overloaded paint and dip them in water, don't keep them there for more than two days.

you said
"What thinner do you suggest is best."

Nedless to say, thinning the paint naturally follows the old rule "fat on thin", and generally breaks thinning into two big steps, thinning for the first and second layers.

FIRST LAYERS
I assume that you mean the thinner you wanted to use in the underpainting. When thinning paint for the underpainting (my advice was to use acrylics for that) you can use the odourless "esscence de petrole" (I should say that even though you can't feel it, that doesn't mean your brain cells can't, so stick with acrylics and you'll live longer). Using only a thinner for the underpainting is no problem since you are making the paint lesser fatty, and that is what you strive for.

SECONDARY LAYERS
However, if you want to thin the paint like a glaze over the final layers of the painting you shouldn't and I repeat shouldn't use a thinner alone - you will destroy your paint. One thing to remember actually, is that the paint is never as good as it is in the tube, and if you can get away by not diluting it, then don't. As soon as you start diluting it, you are lowering its quality. Only thin the paint when you absolutely have too so that it suits your technique. Some people thin the paint ruthlessly, completely destroys the binding of the pigments and then, try to "fix" the paint back by "backbinding" it with other chemical mediums (there are too many to mention, too many useless and confusing.); what is the point with that? However, if you want to glaze, you must use a medium, which chemical compound acts like the paints. There are many good mediums out in the market that are excellent, for that. they are usually a mixture of oil, e.g. linseed oil, turpentines and "harts"(swedish, i dont know the Englis for it) If you want to mix your own, you have to be careful what to use. You must know how the different ingredients will behave and react, especially over time. One recommended mixture is 1/2 sun oxided clearified linseed oil (if possible, buy coldpressed, it is the cleanest, but most expensive too, unfortunately) and 1/2 turpentine based thinner. Raw clearified linseed oil that is non sun oxided will yellow and wrinkle much much more, and is therefor not recommended as much as the former.

Hope that helps a bit
Pierre

[MadSamoan]

You could use some of the off the shelf brush cleaners that they sell at art stores or a gentle dishsoap like Palmolive. To protect the brush hairs, you can use a leave in hair conditioner or vaseline petroleum jelly and shape it to its original point/shape.

[johnyd]

Lunatique: Thanks

Markus: Thanks for the link, I will go through it once I get some time

pierre: Yes that's why I mentioned Alla-Prima in the message.
I dont want to bother with acrylics. I want to see how well I do with only oils.

In acrylics I usually paint under painting very watered down to define the volumes then render with colors.

This is the fist time I will be painting with oil in 2 years so I forgot everything What I am thinking is right of the bat just start rendering with tones colors etc. But I am just afraid that if I go over a stroke with a thinner layer while painting that paint will later crack when dry.

By thinner I meant just to dilute the paint while painting, becuase out of the tube it's quite thick.

Your method I would have to paint very thin under painting and wait a few days untill it dries and then start modeling. The problem is I dont want to wait.

I tried regular soap, the oil paint thick inside the brush is hard to wash, that's why turpintine is my choice.

MadSamoan: Thanks I have that soap but haven't tried it yet with oil paints, thanks.

[Lunatique]

Here are a couple of threads from the past that contains relevant information to this topic:
http://www.sijun.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=3&t=002956
http://www.sijun.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=3&t=002660

[ May 21, 2002: Message edited by: Lunatique ]