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earful
01-30-2002, 12:37 PM
perhaps someone could tell me why my oil painting is getting an effect of the paint separating on the canvas in some places and not in others. It almost looks like an oil and water separation. Also, in some areas of the background, the paint is still very tacky after at least 2 months of drying time. I would hate to chuck this painting since it isn't an altogether bad piece of work (for me). Any ideas would be greatly appreciated. I don't know how to correct these problems, if that is possible. The medium I used was 1/3 stand oil. 1/3 grumtine, 1/3 linseed.

Einion
01-30-2002, 06:06 PM
How is the canvas primed? If itís acrylic "gesso" and the surface was a little glossy (very common) it might be that the slick surface won't let your oil paint adhere properly - as the surface oxidises it shrinks, pulling the wetter paint underneath away from the support.

How did you build up the painting? Did you work in one layer or a number and if so how many and did you work fat over lean?

Thicker applications of paint can take over six months to dry depending on local conditions and stand oil slows drying but depending on how you define tacky it does sound like you have a problem - the surface at least should be quite dry to the touch by this time.

BTW why did you mix stand with linseed?

Einion

earful
01-31-2002, 03:10 PM
I used several coats of acrylic gesso prior to applying thin layers of paint for the underpainting. An art teacher recommended the use of stand oil along with linceed and grumtine. I tried to stick to the fat over lean principle. I did notice that the paint went on with a sort of drag to it rather than a smooth flow of paint to canvas, if I am explaining it properly. I have no idea why it would go on that way but it was difficult to handle. Any ideas as to what caused it to go on that way?

Mario
01-31-2002, 07:14 PM
sounds like you might have too slick a suface that the paint is slipping off of...also, perhaps you used too much thinner (better don't use any) in the problem areas...and what the heck is Grumtine?

Einion
02-01-2002, 06:56 PM
The drag you describe is actually not a bad thing: it implies the primer surface wasn't slick so I'm confused about what the problem might be here, sorry.

Mario, Grumtine is a Grumbacher low-odour turps replacement.

Einion

Trimoon
02-02-2002, 11:18 PM
You may have silicon contaminant on the canvas .

belladonna
02-10-2002, 03:01 PM
I have had this problem before once when I kept my loaded pallet to long in the fridge. Have your paints ever been stored in the cold? That could cause this. Cold can break down the adhesive qualities...