How to Brush Light Grey?

Be careful with the use of a retarder, Otto, particularly if you're attempting to use it to "thicken" your paint. It's sole purpose is to prolong or delay the drying and curing of your acrylic paints so that you can come back later to layer highlights and shadows and still be able to blend them. It's a technique a lot of figure painters use, particularly with faces, where there are several different layers of paint to give shadows and highlights which require a bit of blending at the edges. Slowing the drying time becomes more important in this case, so just a touch of retarder is added. It's not really necessary with a base coat of color.

If you're thinking that your paint is already too thin to begin with, don't add anything else to it, like water or thinner. You're just thinning it even further and making it worse.

With Model Air, the stuff starts off considerably thin when compared to the Model Color line so that it can be airbrushed straight from the bottle. If you use a brush, dispense a few drops of the paint onto a dry palatte and let it sit for a while to allow some of the carrier to evaporate off. Give it ten minutes, then check the paint on a piece of scrap sprue. If it's still too thin, leave it alone for a while, then check it again until you find a consistency that you can work with.

If it becomes overly thick, add a drop of either water or the thinner to even up the consistency, but only a drop. It's far too easy to over-thin the mix, so work slowly and purposefully until you find what works for your situation at the moment.

Don't paint your parts until you're absolutely satisfied with the mix you've created, but use the sprue runners and frames as testbeds until you are confident. 

I did not use any primer. When I first made the post, I made the mistake of trying to paint it over a dark grey, however painting it on light colored sprues hasn't helped either.

It seems that I have tried almost everything: straight out of the bottle, thickening it with Vallejo retarder, thinning it with a couple drops of water, both at the same time, etc. I have recently bought Vallejo Thinner Medium, so maybe that can help, however I have no idea how to use it, and applying a drop (along with 2 drops of water) to 2 drops of Vallejo Model Color White seems to make it too thick and gives me brush strokes.

What did you prime with- that is, what is the paint going over?  I find thinning ratio is as critical for good hand brushing as it is for airbrushing.

oldermodelguy

I agree with Greg, you want Model Color. There must be a grey that is close enough and then by the time you weather it and all it won't matter anyway. Even if it's half a shade dark though you could mix in a little MC white. If too light a spec of black goes a really long ways. Even real planes have variations according to weathering, age etc... Just sayin.

 

Yeah in the grand scheme of things it's not a big problem, but it throws a big wrench in buying Model Air (who's color range and matches I love) if I can't get this grey to work and don't know I'd other colors will fail as well.

Greg

In a nutshell, handbrushing Vallejo Model Air is an exercise in futility.

Adding retarder probably isn't helping, it may be making things worse.

I've had some success leaving a drop dry on my pallet for some time, then trying, but that only works for itsy-bitsy jobs and tiny touch-ups.

I looked for USAF Grey in Model Color, which you may have already discovered handbrushes like a dream, but I didn't find it. If it doesn't exist exactly, the Model Color line has more shades of grey than any other I've seen. You may be able to find something close enough without having to mix the color.

Other Model Air paints such as 71.300 Glossy Sea Blue and 71.010 Interior Green brushed on pretty much perfectly. It really sucks that the hand brushing performance isn't consistent since now I don't know what works and doesn't, and Air has a better "fit" to its range than Model Color

Cadet Chuck

I believe Valllejo Air is meant for airbrush use only, no thinning required.  That may explain your problem.  Have you tried airbrushing it?

According to the Vallejo website:

"Model Air can of course also be applied with a brush."

I haven't tried airbrushing (not exactly sure where it is).

I agree with Greg, you want Model Color. There must be a grey that is close enough and then by the time you weather it and all it won't matter anyway. Even if it's half a shade dark though you could mix in a little MC white. If too light a spec of black goes a really long ways. Even real planes have variations according to weathering, age etc... Just sayin.

I believe Valllejo Air is meant for airbrush use only, no thinning required.  That may explain your problem.  Have you tried airbrushing it?

In a nutshell, handbrushing Vallejo Model Air is an exercise in futility.

Adding retarder probably isn't helping, it may be making things worse.

I've had some success leaving a drop dry on my pallet for some time, then trying, but that only works for itsy-bitsy jobs and tiny touch-ups.

I looked for USAF Grey in Model Color, which you may have already discovered handbrushes like a dream, but I didn't find it. If it doesn't exist exactly, the Model Color line has more shades of grey than any other I've seen. You may be able to find something close enough without having to mix the color.