Oil Wash leaving a dull gray film after drying

[panzer948]

Just a general question on a problem I am having doing a wash or pin wash on my models using my new set of Windsor Newton oil paints. A few years back I always used a cheaper brand of oil paints and never experienced this so not sure if the higher price oils that so many recommend are the cause or something else.

Basically, after completing the model with Acrylics and sealing it with a clear matte (usually testors dullcoat). I add your standard wash or pin wash using my darker colored oils (mostly black or burnt umber) mixed with diluted odorless mineral spirits you can buy at any hardware store. I use the mineral spirits since Turpentine can sometimes damage the underlying coats, although back in the day with the cheaper oil paints I am pretty sure I was using turpentine. It looks great going on but when the wash dries, instead of the nice dark color left in the recess areas I get what looks like a dark gray film that nearly blends in with your darker color base coats. It seems to do the same with all my darker colored oil paints. Not what you want to see in a wash. What could I be doing wrong to cause this? I recall a dark oil wash would leave the actual color behind in the recess areas or wherever it was applied. Not a gray film. Could it be the oil, mineral spirit, reaction with the paint? It seems to do it both on surfaces that I had added clear and others that I left without clear coat. For acrylics I am using either Tamiya or Vallejo.

[colin]

Washes need to be put on a gloss finish, especially panel line washes, Putting them on a matt surface means they will stain the matt varnish.

What your getting is like a tide mark, where the wash has soaked into the rough finish of the matt varnish and stained. this can be used as a weathering finish in it's own right, normally by armor builders to create stains/wear and the like on a vehicle.

Also it's best to use a acrylic varnish if your using a oil/enamel wash as the thinners won't attack that type of varnish, I think testors varnish is a enamel based one so white spirit/turpentine will attack this

[panzer948]

Great response. Yes, that has to be my problem. Plus the fact my favorite Matt Clear Coat is enamel/lacquer based. I will switch to Future for the clear coat just before doing the wash. I can always use the Matt Clear to seal everything back up at the end. Thanks again for your help.