WSO on top of old oil painting

Hi everybody!

I'm new to this forum and I'm new to water soluble oils. I used to paint traditional oil more than ten years ago, but then I gave up for many different reasons. Now I've started painting again, but I need to use wso now. I recently made a lot of changes to one of my old paintings, which was painted in traditional oils. My intuition says that the painting could become unstable, and it doesn't really matter since the painting was quite boring before I changed it, but I'm wondering about the posibility of changing others of my old oil paintings. Is it possible to use wso on top of old oil paintings as long as I keep to the rule of fat layers on top of lean? Or is it bad to use wso on top of pure oil paintings?

I also want to know your opinion about mixing different brands of wso. I've bought both Cobra and W&N Artisan, and they seem to be working very well together. Then I read that W&N don't recommend mixing their products with other brands, but I don't understand why, as long as the paint behaves as expected. Could there be long term problems because of mixing the two brands?

Thanks, I'm looking forward to your answers!

I can't speak as an expert on the topics you bring up, but I would ere on the side of caution. If there is an older unwanted canvas in traditional oils that you could test before applying the WSO onto your other painting, I would try that first.
Same with mixing brands. My impression (non expert) is that each brand is formulated differently, unlike traditional oils. I purchased a few tubes of Cobra and Holbein (if I remember correctly) and each have their own mediums. I will keep them separate from each other, but will try a small painting with each. They seem to be intended to be self contained systems.
Same with Artisan, which I normally use.
Good luck!

Welcome to the forum. I mix different brands all the time and have no problem. I use mainly W/N, cobras, and Holbein duos. I never use water with them but thin leaner layers with W/N thinner and fatter layers with walnut oil.

As far as painting over oils, I would put a thin film of walnut oil first and then use the paints out of the tube without any use of water. The paints themselves do not contain water. You are also able to mix regular oils with WS oils if you want, but they loose their water solubility.

I'm sure other members of the forum will have more in put for you.

Here is link to an article I've written on using WS Oils in place of traditional oils that might be of interest to you.
http://www.squidoo.com/oil-painting-techniques

Feel free to browse the forum to gain more insight.

Judy

Thanks a lot for your input! I avoided using any water when I worked with my old painting, and I also remember reading somewhere about one of the brands I'm using that it should work with traditional oils as long as you avoid water. I think it was W&N Artisan. I take that as an indication that it should be possible to use wso on top of traditional oil paint, but I'm really uncertain, and that's why I'm asking the question here. On the other hand, I think it seems wrong to put a paint which dries faster on top of a slow drying paint, and I believe that I'm doing exactly that when I paint with wso on top of oil.

I'll certainly take the advice to browse the forum! I know from experience that a place like this can be a wonderful source of knowledge whenever you need to know more about a topic!

How long ago did you paint the original oils? That would be important to know as to how dry they are. Also, WS Oils do not necessarily dry faster than traditional oils unless, perhaps you used an excessive amount of oil to fatten the top layers of the original. You might want to research the individual brands of WS Oils so you have a better understanding of their drying times.

I do have some charts and discussion about drying time on my art website. You might want to look there. Here's the link.

http://filarecki.com/oil-paint-drying-times.html