Forum adverts like this one are shown to any user who is not logged in. Join us by filling out a tiny 3 field form and you will get your own, free, dakka user account which gives a good range of benefits to you: No adverts like this in the forums anymore. Times and dates in your local timezone. Full tracking of what you have read so you can skip to your first unread post, easily see what has changed since you last logged in, and easily see what is new at a glance. Email notifications for threads you want to watch closely. Being a part of the oldest wargaming community on the net. If you are already a member then feel free to login now.

Ok, I've done this for years, water down black paint to use as a wash, when it dries, dry brush on the other colors And on and on. Sometimes it. Works great and the low spots hold the color, other times it's like the paint rises and darkens the high spots and leave the low spots light. Why does it do this? How do I prevent it?

Not sure what you mean. If it's thinned, it should simply run into the recesses and stay there until it dries. If you're getting pools of wash on flat surfaces, though, the easiest thing to do is use the corner of a sheet of tissue or a moistened paintbrush to just soak up the paint, and if need be paint it back into the recesses. Or just paint directly into the deeper areas in the first place, that ought to do it.

Just checking, you are leaving the models standing upright to dry, aren't you? If not, then the wash will go into all the wrong places.

Make sure when you put ur piece down to let it dry the shade/paint doesnt move. It maybe where you want it when its in ur hand but once you put it on the table the shade may move and dry in a different spot.

I know this problem and it's tricky to solve.
In my experience 2 things come to mind;
1) The most obvious one is that maybe the paint is too thin? Many times I've thinned down paint too much only to discover that it's basically water! Most colours don't cover first time,even black,so it's debatable if you need to really thin them down much.
2) At the other end of the spectrum;perhaps the paint on the model has covered too well leaving the wash nothing to grip onto? There are colours(especially really opaque ones)that seem to dry with a very water resistant surface rendering any wash hopeless.
What I'm doing at the moment is blending rather than washes/not using a host of shades just going from dark to light by means of white added to the main colour until I get to a point I'm happy with.
If you want to use washes I'd recommend three and I find them much better than Citadel or Vallejo. All you need are Army Painter's Soft tone,strong tone and Dark Tone,and they do stay in the recesses!

the problem is one of surface tension...
sometimes the very thin paint does "pull" itself out of the cracks as it dries, especially as the water in your mix evaporates during the drying process...
a tiny bit of dish-washing liquid soap in a homemade wash will keep this from happening...
this is an old trick that has been used for decades, but now people are using acrylic medium to thin, which doesn't evaporate like water does...

personally, i like to mix in some P3 Armor Wash with black, as it is already thin, but a full-bodied color...
the black paint knocks back some of the glossiness of the Armor Wash, which is nice, since i photograph before i varnish...

cheers
jah

'

As above, the surface tension can vary depending on several factors (amount of water, temperature of environment, humidity etc).

For vehicles I have been mixing black paint with acrylic gloss varnish and then adding some thinning medium as well as some water to get a nice ink-like consistency.

It holds on to the cracks and crevices very well. As a bonus, gloss varnish and thinning medium are both very cheap at the art store.

I have also heard of people using Future floor polish as a medium (it's been replaced with some Pledge product, since, but still readily available), also very cheap, though I have yet to pick any up to test this out.

One possibility that I don't think has been mentioned yet... if you're applying a wash over a sprayed or airbrushed base coat sometimes the wash gets drawn to the raised surfaces. It happens if the paint is slightly porous and/or rough.

What happens usually is the wash initially gets drawn in to the crevices, but as it dries it gets drawn to where the basecoat is thickest as it soaks in to the porous/rough basecoat, which if you sprayed the basecoat is the raised areas.

I had this happen a lot with my tyranids because I'd apply a wash straight over my sprayed primer.

Yeah surface tension and science and junk.
As a quick/cheap fix try adding a little liquid hand soap to your mix of paint and water.
Should do the trick.

I'll try the soap trick, thanks! Just. Drop I take it?

Yeah, just a touch, you don't need a lather or anything.
If you've ever used GWs inks or washes you'll notice that they can get quite foamy after a really good shake.
It's kinda the same thing.

Good tips here, thanks all above.

+1 to using dish soap to help break up surface tension. Works for me.

Why not use Nuhln Oil instead of black paint? The results for Nuhln are awesome. And you can dilute it with Lahmian Medium to make it less opaque.

Jah and others are spot on about surface tension. Essentially, it's no different than water drying in rings rather than evenly, because as it evaporates, water has a tendency to pull to itself into little drops and pools.

Dish soap works, the old Klear floor wax worked really well (it's just polynonylmethacryalate), and Liquitex Flo-Aid and various mediums also work to make it so that the paint doesn't dry with rings.

Something like Nuhln Oil (or, for instance, AP Strong Quickshade) is a better product for doing black washes because at its formulated opacity,it's much runnier and will naturally slip into the crevices more than thinned paint will, which just saves you a whole lot of work.

 Talys wrote:
Why not use Nuhln Oil instead of black paint? The results for Nuhln are awesome. And you can dilute it with Lahmian Medium to make it less opaque.

Jah and others are spot on about surface tension. Essentially, it's no different than water drying in rings rather than evenly, because as it evaporates, water has a tendency to pull to itself into little drops and pools.

Dish soap works, the old Klear floor wax worked really well (it's just polynonylmethacryalate), and Liquitex Flo-Aid and various mediums also work to make it so that the paint doesn't dry with rings.

Something like Nuhln Oil (or, for instance, AP Strong Quickshade) is a better product for doing black washes because at its formulated opacity,it's much runnier and will naturally slip into the crevices more than thinned paint will, which just saves you a whole lot of work.

Just an FYI, the problem I was describing (I'm not saying it's THE problem, but it's a potential problem) is not a surface tension issue, it's base coat porosity issue. I was getting my wash settling on raised surfaces even though it was specifically designed wash (initially Devlan Mud than I swapped to AP strong tone).

The only way I solved it was to make sure the paint was more wet when being sprayed on and/or quickly and lightly over coating the models with a hairy brush after the sprayed primer coat had dried.