Question Re Water Mixable Oils

When your painting has dried and you want to go back into it, what do you treat the surface of the painting with? ( I do not use any water with mine.) Have not been able to find any info on this, so if you know of a good book, or blog, on working with Water Mixable Oils, that would be appreciated also!

Here is the WN products: which is the only water sol oil I tried.

Once water-solubles are dry, they are like any other oil paint. There are many magical incantations for going back into dried oil paintings up to and including rubbing them with a cut onion… but the best is simply to scuff the surface with fine sandpaper or wet-or-dry paper. This provides a roughed-up surface that has enough tooth to hold subsequent layers of oil paint. I prefer the wet-or-dry, used with water, as you accomplish two goals: roughing the surface and washing it.

It’s actually the same process that used to be done when re-painting houses or interior walls, in the days when the paints were oil-based. The motto was that preparation was 9/10ths of the paint job, and preparation began with washing, then dulling the surface to ensure that the new layer can bond to the old.

If you’re using toxic water-solubles (true cadmiums, for example), you probably want to wear a dust mask while roughing up the surface. In fact, a mask is a good idea in general while sanding anything, paint, wood, metal, etc.


I took a class with Cindy Procious, who paints in layers and all she had us do was oil out the painting. She uses Walnut oil Alkyd so we painted it on the area we were going to be working on, then took a makeup sponge and wiped it down. Then continued with the next layer. The reason to do in sections, if it applies to the painting you are doing is so while that section dries you can do another section the next day while the other one dries. This also brings up the hues and values so you can better judge what the next layer needs.


Thanks so much Sunny! I’ll check that out!

Thanks Dave, the onion method would make me cry!!! :slight_smile: Thanks so much for the sandpaper tip, will have to try that on some of my older paintings. Thinking for those that have just dried out for a couple of days though, that I need to go back into, willgo with the oiling out. Appreciate your input!

Thanks Elizabeth, I have the Walnut Oil Alkyd, so will just go with that then, and will also look up Cindy’s work! Thanks for responding!

I’ve been painting with wmo’s for several years and, as with regular oils, a coat of retouch varnish can be applied and painted over. I also use retouch varnish as a finish varnish as you don’t need to wait six months.

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Thanks so much Madeline! So about how long do you wait after the painting has dried to apply the retouch varnish? I had bought the Cobra Spray Varnish, but that would simplify products!

Retouch varnish can be applied within a day or two, regular varnish after six or more months.

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Thanks Madeline, appreciate your getting back to me!