On my last model I noticed that when cured - my oil wash looks grainy - the pinwashes flow away and result in a sand grain look.
Since I am confined to being a living room modeler I recently switched from Mineral Spirits to odorless Turpenoid because of the odor.
I’ve changed nothing about the oil mix ration from previous models which did not have that grainy look.
any ideas what could be causing this look ? Is it the Turpenoid ?
Are you gloss coating the surface of your model first? The wash will flow better over a glossy finish. If you do it over flat paint, you’ll get the graininess and much of the pigments will remain on all the surfaces, instead of just in the recesses and raised areas.
Yes, I did. The wash on my previous models I did the mineral spirits over a clear coat which worked nicely. I even went bought a Super Gloss for my current project but i am still getting that grainy look as opposed to the nice even look that I achieved before. I am wondering if Mineral Spirits are superior to the Turpenoid since i really didnt change anything …primer, Tamiya Acrylics, etc is all the same- even the oil colors are from the same tube.
You can see the difference here - the oil wash lays nicely on the Tiger recesses but the bolt washes from the SU-122 have those grainy “rings” which frustrate the heck out of me today.
Mel, I’ve noticed the same thing lately with my oil washes, even over a high-gloss finish. They would appear blotchy, leaving more pigment in some places than others along an even surface. What I attributed it to was inadequate mixing of the pigments and the thinners. I’ve since started doing my washes with MM enamels thinned with mineral spirits at a ratio of roughly 1 part paint to 8 parts thinner, and I’m much more satisfied with the results. I do it over a Future gloss coat and the wash pigment remains evenly spread out over it’s entire length once dry, and the results are very subtle, not overpowering.
Thanks for the reply Mike.
I am gonna try and tweak a little bit with the mixing ratio eventhough i coudl swear I had the same ratio when I did the Tiger tank. Maybe I should keep a little bottle of mineral spirits handy, too.
You might have a compatibility problem between the oil in the paint and the turpenoid. Mineral spirits comes in two varieties, regular and odorless. Try the odorless.
It could also be inadequate dispersal of the pigment and oil, which you can cure by vigorous aggitation.
Finally, smear some of the oil paint, straight from the tube, on a flat piece of glass or glazed ceramic. Feather the smear to a disappearing edge. Look for graininess there. If there is none, then it’s a solvent problem. If there is, then the oil paint may be too old. (Although they should last for a very long time if kept properly.)
Ross,
Thanks a bunch for the detailed reply. That is very helpful information and I am sure that is gona help me figure out exactly what caused that grainy look.