Fact or fiction regarding Oil paint?

[shakes]

Hi everyone, I had a quick question regarding Oil paints. I've often heard that it is necessary to seal an acrylic painted miniature with varnish before using oil paints for details, washes, weathering, etc. Is this true? I don't think it is, but would like confirmation before skipping the step. I also thought that it could depend on what solvents you're using? I'm using Winsor and Newton odourless spirits, or something like that.

Cheers, Shakes

 

[MAXXxxx]

I used oils without sealing the acrylics first without problem, so it's no necessary, but still it would be a good practice.
So my advice: seal it, then oils. Especially as sometimes the varnish helps (like gloss for pin-washes, it helps a LOT)

 

[gohkm]

I would assume you are making an oil wash with white spirit? If so, varnishing may help protect the underlying paintjob, as white spirit will attack paint. Regardless, once applied, it is not a good idea to move your oil wash around.

 

[BloodFather of Kharnath]

I've put a lot of energy Into researching oils lately, so I definitely understand your confusion here. Some state that they varnish, some says it is unnecessary. The guys at Massive Voodoo use turpentine, a fairly volatile substance, and they do not varnish their acrylics before applying oils. However, putting acrylic on top of oils requires a varnish, according to them. So if you put a base coat of acrylic and follow that up with a bit of oil shading and highlighting, no need to varnish. However, if you want to further shade or highlight with acrylics on top of those same oils, a varnish is necessary (all of this according to MV). Watch their video, for me it was very informative.

 

[Ritual]

However, putting acrylic on top of oils requires a varnish, according to them.

In traditional art you get taught to never put acrylic paint over oil paint, as oil paint will continue to evaporate and slightly change for years and years. Acrylic paint, which does not change anything after it's set, would then start to crack. I am not sure if this is applicable on miniatures and since the effect wouldn't be visible until many, many years after the figure is painted, I'm not sure anyone has found out yet... I haven't painted with oils myself, but I'd be wary to put any acrylic paint over oil paint, at least on larger pieces where I'd guess you could have similar effects as on canvas. If you base with acrylics and then use only oils after that, you'll be safe. You can glaze with oils too, only it's a hassle with the very long drying times.

 

[BloodFather of Kharnath]

I have heard this as well and so yes, perhaps not wise to mess around with.

 

[Ritual]

I'm not sure if you'd need to varnish before glazing with oils... I don't know what the thinner used to thin the paint used for the glaze would do to the underlying layer of paint. Maybe someone who has painted with oils can answer that?

 

[Matney X]

I always do -- partially because I tend to use oils over an airbrushed base coat, and partially because I had issues with oil washes eating my acrylics when I tried to clean them up. Whether it's really necessary or not, it makes me feel better.

 

[oistene]

As long as you don't touch the paint, you should be okay. The oil can make the acrylic liquid again - not liquid enough to make it runny, but if you touch it, you' might be screwed. Varnish can do the same thing.