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ElDuchen
03-14-2012, 04:25 PM
I am learning the ropes of using an airbrush and tweaking my mixing rate of paint:water. I find that I get a water splash when I first start painting. I can work around that by spraying away from the model at first, but I was wondering what do people use as a mixing medium when prepping paint for their airbrush?

frommage
03-14-2012, 05:33 PM
Good old cheap Windex...Man this product has thousands of uses, it keep my wet pallet from producing molds and It also clean most of my home!!!

RebelGrot
03-14-2012, 05:35 PM
Good old cheap Windex...Man this product has thousands of uses, it keep my wet pallet from producing molds and It also clean most of my home!!!

I keep hearing a lot of good things about Windex. Does anyone know if it's available in the UK or, if not, what the UK equivalent might be?

beno
03-14-2012, 07:05 PM
I never got round to even looking for windex here in the uk - depsite hearing great things about it! I picked up a big bottle (half litre I think) of Tamiya thinners, probably pretty similar stuff in the end. Works fine, but then again I find water works ok as well for most of the paints I use - Vallejo - which seem to have some solvent breaking the surface tension in them anyway.

Mistress of minis
03-15-2012, 04:54 AM
Any blue window cleaner (without ammonia!!) will do fine, Windex is just hte brand name and Ive had the generic stuff do the same things.

Rubbing alcohol (I believe its 'medicinal spirits' in the UK) also works well and makes the paint dry even faster(a bonus in humid areas- but not in dry areas where it can dry before it even hits the miniature!).

ElDuchen
03-15-2012, 11:13 AM
For the moment, my main paints are all Citadel paints. What ratio of windex to paint do you find works for you? With the water, I am at 3:1 water:paint, which may be part of my problem, but if I don't thin it enough my compressor won't push the paint through.

Meph
03-15-2012, 01:41 PM
Another good medium is demineralized water, the cheap, odourless kind used for ironing. Works very well I think. Also, Vallejo's thinner is very, very good and comes in 200ml bottles.
For ink you definitely need something fully transparent as not to mess up the tint. The demin. water works perfectly.

The ratio is a bit dependent on the thickness of the paint, as that can vary from bottle to bottle. in general you want it just that little bit more runny than you're comfortable with. The thickness of mild is a good target to aim at.

Even if it's just a little bit too thick you'll notice that the nozzle clogs up pretty fast. You should be able to spray a few minutes before your spray diminishes dramatically. And build up your layers, never try to go for just one coating. Using a thinner like demineralized water will dry out a lot faster than regular water once sprayed.

Mistress of minis
03-16-2012, 12:25 AM
GW paints are kinda...bad, at being airbrushed. You'll have to experiment to get the right ratio as what works for one color will not work for the next (unlike vallejo & reaper which seems a bit more consistent between hte colors).

The size of the nozzle on your AB is also a factor with the thicker paints. .3 is about as small as I will even try for paints not specifically for an AB. For the really goopy stuff like the GW foundations stuff even a .5 can clog up frequently.

The general mantra for airbrush paint is 'consistency of milk'. An thicker and you get clogging, any thinner and it takes numerous coats.


Ultimately, experimenting is the name of the game, finding out what works for you, the brush you have, compressor, paints and mediums makes for a huge number of variables. Threads like this can help give you ideas where to start, but the fine tuning is up to you :)

beno
03-16-2012, 08:20 AM
The general mantra for airbrush paint is 'consistency of milk'. An thicker and you get clogging, any thinner and it takes numerous coats.


I would say that the consistency of milk is a little misleading - I never thought it made much sense. When I started out airbrushing I'd try to make it milk thin, but it would end up spattering all over the place because it was far too thin!

I use mine for priming just about every model, with Vallejo's Surface Primer, and have found that one drop of water to two parts primer is spot on. This is much thicker than milk I think, but works perfectly!

Trial and error is the best way. My advice would be to start with one large drop of water in the cup and three large drops of paint and stir til its a consistent mix. Test spray on some paper; if its too thick (probably) add a small drop of water and stir it thoroughly in... keep adding water in small quantities until you can spray an even, smooth line. Now go paint your models!

Regnir
03-16-2012, 12:52 PM
I would say that the consistency of milk is a little misleading - I never thought it made much sense. When I started out airbrushing I'd try to make it milk thin, but it would end up spattering all over the place because it was far too thin!!

It's not necessarily about how thin it is though, in your case. You can spray incredibly thin paint if the PSI regulator on your compressor can adjust well below 10 PSI.

I often times spray with an Iwata Custom Micron(model CM-SB) which is a .18mm needle/nozzle combination. I spray a mix of GW and P3 paints, and generally have to thin about 1 part paint to 15ish parts thinner(I use Windex or Testors Acrylic Airbrush Thinner, whichever I tend to have on hand). The trick to spraying this thin is to drop your pressure dramatically. I tend to spray at around 5 PSI with the CM-SB and 1:15 citadel paint. This is amazing for pre-shading 28mm infantry models, and even some vehicles.

For the majority of my work, I use an Iwata HP-C+, and almost always use a straight 1:1 thinning ratio. The HP-C+ is a .3mm needle/nozzle combination. I tend to pre-mix my paints in empty Vallejo style eyedropper bottles that I pick up from the internet in that 1:1 ratio, and then further thin them down in the airbrush cup just prior to spraying. Works out quite well.

Citadel Foundations and Metallics are a different story. The metallics I tend to keep thinned at 1:2 or 1:3 for a nice even spray, and Foundations tend to be closer to 1:5 or so.