Wash

[kruker]

I need help with finding a wash that will just work like a pin wash, therefore not leaving unnecessary "weathering" marks. I tried Mig and AK enamel on top of glossy acrylic laquer, but no matter how much I try to get rid of the unwanted deposits using white spirit, I always find it to darken the painted surface. Vallejo acrylic wash is terrible and too "heavy". Once dried it is almost impossible to wash it off. The best results I had so far were with Citadel Nuln oil which seems to be acrylic. However, I haven't found a way to wash it off from unwanted surface.
Can anyone recommend any product that will just simply make shading instead of weathering?

[biggles2]

After painting I gloss coat with Future (Pledge) then use an overall wash from artists' tube oils (black) and white spirits. The wash will concentrate in and around raised and engraved details. But you will still have to remove excess oil wash from flat areas with a constantly cleaned brush (before the oil wash dries) - you sort of sweep the excess pigment into the detail areas. You could also brush clean white spirits over the whole model, and with a very fine brush (5-0 or smaller) do a pin wash. The spirits' wash will help the pin wash to flow into detail areas. You will still have to drybrush after to sharpen up some details.

[wefalck]

'Wash' means applying a thin, translucent layer of paint and has nothing to do with washing or wiping off a layer of paint that has already dried. I am not so familiar with the 'modeller's speak', when it comes to painting techniques, but assume that by 'pin wash' you mean letting some dilute paint running into depressions or corners ? Now for this one needs to understand a little bit of surface physical chemistry. It has something to do with surface roughness and the surface tension of the liquid in relation to the surface roughness.

I am not sure that a gloss surface is a good basis for any kind of washes, due the fact that aqueous liquids will form droplets, rather than a uniform film. A rough, i.e. matt, surface will 'pull in' the wash. That is, when you use water-diluted acrylics on acrylics. If you use oil washes on enamels or glossy acrylics the situation is different, because the organic solvent-based washes have a different surface tension.

Having said that, I think the way forward would be to let very dilute paint run into engraved lines and the likes using a very fine brush or a drawing pen, thus building up layer after layer until the desired depth of colours is achieved.

When applying 'broad brush' washes, one also would use very dilute paint, which can be washed off with more water and a clean(ed) brush before it has been dried (talking about acrylics). This allows to build up subtle layers until the desired effect is achieved.

[kruker]

Thank you both for such comprehensive answer

[biggles2]

The difference between oil washes and acrylic washes is that after the oil wash has dried, excess oil pigments can still be removed with a brush moistened in clean thinner. When an acrylic wash has dried it is permanent. Acrylic washes also are more likely to leave drying marks, or stains.

[wefalck]

What do you mean by 'drying marks' or 'stains' ? I don't seem to have a problem of this kind.

The fact that solvent-based paints can be removed with the respective solvent/thinner means also, that building up of layers of washings is not so easy. One has to work very fast when applying the next layer, so that the abundant solvent does not re-dissolve the previous layer(s).

[biggles2]

Who uses multiple layers of washes?? One overall wash is sufficient, and when dry, followed by selective pin washes to accentuate detail. But you can remove any unwanted wash pigments after the overall wash and before the final pin wash.

[wefalck]

Multiple washes are the whole essence of the technique - you can slowly build up depth with variations according to location; you can also use different colours to further add depth and variation ...

[David Griffith]

I would also suggest using artist's oil paints, but try diluting the paint with artist's turpentine rather than white spirit. It is much faster drying than white spirit, and this makes it easier to work multiple layers. It can be removed and moved around with a damp brush, and like white spirit, does not leave tidemarks.

David

[RichardP]

Something I'm not seeing clearly in the replies (maybe that's just me) is the need to ensure that the wash does not interact at all with the base paint finish. If you use the wrong type of wash then you will get tide marks (or darker staining) where the solvent (? thinner) soaks into the paint. The recommendation is to seal one type of paint (enamel/acrylic) with the opposite varnish but I have found that some 'acrylic' finishes will still be affected by an some types of enamel thinner.

Biggles2 mentions the use of Future which I have found to be pretty much impervious to any solvent if given time enough to dry properly (a few days); not only does it resist penetration of the wash, it's smoother finish assists the wash in running along surface features where there is a corner or groove etc. Personally I like Future (on any type of paint) as a protective selant applied with a wide soft brush rather than airbrushed, over which I can apply oil or enamel filters and washes (and I am thinking of the techniques described by David Griffith's books as I write this), which do have not surface tension issues that you may get with water based equivalents. Additionally, let each effect dry before moving on, I have found that what looks good wet can look overdone when it dries; with that Future layer you can apply thinner sparingly on it's own to tone things down without affecting the original paint.

As far as I am aware, if you achieve a good result with on wash effect then you can seal that in with Future before moving on to the next effect i.e. once you have applied filters then consider (it's not essential with a deft touch) protecting the filters with Future before moving onto a detail pin wash.Finally the use of dullcote or preferred matt cote seals the deal. Note that additional protective coats and/or matt finishes will have slight visual effects on the filters and washes so experimentation is needed.

[kruker]

And what about Clay based was such as ex. Ultimate weathering wash? Any experience with that kind of wash?

[wefalck]

I assumed that the compatibility of the different paints had been tested before.

Personally, I am trying to avoid using too many different types of paints. In fact, these days I tend to use only water-based artists acrylics. Messing around with organic solvents, particularly when cleaning the airbrush is just inconvenient.

I am also avoiding to apply too many layers of paint and varnishes. I would hate the fine surface detail and crisp machining I did to be drowned in layers of paint. I realise that sometimes a clear glossy varnish (e.g. floor polishes, such as 'Future') may be called for in order to achieve a particular 'depth' of surface or for technical reasons, e.g. to seal surface pores in matt paints in order to avoid air becoming trapped underneath decals (i.e. avoiding the 'silvering' phenomenon), but otherwise I would rather not apply 'sealing' layers. There is also the risk of otherwise sharp internal corners slowly developing 'fillets'.