[Cassidypaints]

Hello everybody!
I'm Cassidy, a 13-year-old who has been painting with oils for around 8 months now???
Usually, I go with my instincts rather than specific techniques when it comes to painting but this time I face a terrible problem!

A few months I stumbled across a canvas that I had made an acrylic painting of and decided to do a thin wash of Liquid white and blue oil paint to cover
the acrylic painting underneath so that I can could use the canvas again sometime. Fast forward a couple of months and I decide to use the canvas to create
an oil painting.

Once I had finished the painting, it looked pretty good to me and I was really proud. However the following day the painting had begun to crack quite badly in a few areas,
I was distressed and decided to act on impulse, so I re-painted the cracked areas and then proceeded to cover the whole canvas with Windsor and Newton Spray on Matte varnish. Unfortunately, this did not solve the problem and the painting has continued to crack!

(PS. The first picture is the painting before the cracking began, the second picture is the cracking after the varnish was applied.)

Now I'm desperate for help! If anyone can tell me what I can do about this! Thank you very much in advance and I hope you have a great day!

 

[Steve Neul]

If you were painting woodwork instead of a canvas it would be wrong to put an oil based paint over an acrylic paint. The acrylic paint is softer than and more elastic than an oil based paint. I think the liquid white and the oil paint caused the acrylic to swell and then the oil paint being more brittle cracked. I think it won't stop there, I believe the paint will start flaking off. Personally I like the appearance of the cracks but if you don't like it I think the safest fix would be to start over on a new canvas.

Varnishing a canvas can also cause cracks. If you varnish an oil painting before it is fully cured it can cause cracks. Depending on how thick the oil paint is it can take six months to a year for the paint to fully cure. I threw away a couple of paintings yesterday I did when I first started painting. Not knowing anything about varnishing a painting I applied the varnish a couple weeks after painting them. The paint was cracking down to the gesso and flaking off in places and it never had any acrylic paint.

 

[Arduy]

Hello Cassidypaints, I'm not a super expert, but it seams to me like a not following the "fat over lean" rule. A layer of thinned paint dries fast, and shrinks, diminishing in volume over the underlying paint that is more stable on the canvas. I'd take a picture of the painting, and I would redo it again on a well prepared canvas, paying attention to the fat over lean rule. But, then again, this is only my impression.

 

[M Winther]

It's hard to explain. Maybe the "thin wash" was too thin. You could have used white acrylic paint or gesso instead. I don't think it's a good idea to apply a wash of thin oil paint directly on acrylic. You do that on an oil layer.

 

[Ally]

Hi Cassidy,

I think the key thing is that with oil painting you do have to have a good understanding of the basics of building a stable painting (fat over lean/different mediums/different grounds/how to do an underpainting etc.) before you start painting by instinct.

I dont think there is any way to save this painting unfortunately, and varnishing a painting with oil paint that has not cured for between 6-12 months will only exacerbate the problem.

As others have said, use it as source material for a new painting (it's really cool btw!) And use this as a learning experience in how to use oil paints going forward.

Good fortune in your future art!