Correctly thinning Tamiya paint for airbrushing is a simply trial and error process of starting with thick paint and steadily increasing the thinners content until it sprays perfectly.
While this may be a simple task as shown in this article, prior to going through this process you’re not alone in wondering how to thin Tamiya lacquer spray paint and what lacquer paint to thinner ratio you should use.
Using decanted Tamiya lacquer paint in an airbrush has been going on for decades, and is so popular that Tamiya has now given us another option easily accessing their lacquer paints…
Different Sources Of Tamiya TS Lacquer Paint For Thinning
TS Lacquer Spray Cans
The first and most well known option is the good old TS lacquer spray cans.
These paints come in over 120 different colours at time of writing, however we now have a different options with additional colours…
TS Lacquer Jars
What many people don’t realise is that Tamiya now offers their TS lacquer paints in handy 10ml jars.
This makes a lot of sense as many people have trouble decanting Tamiya spray paints into a mixing jar or airbrush.
👍 If you’ve had trouble with decanting spray paints for airbrushing yourself, check out my article that gives you, hands down, the easiest and quickest method for decanting Tamiya spray paint available anywhere.
Additionally, Tamiya have also expanded the range of colours with the TS line, with almost twenty new options.
Note however, that not all TS lacquer spray can colours are available in the jars, nor are all the TS lacquer jar colours available in the spray cans, but there is a reasonable amount of crossover.
Whether the jars or spray cans, these lacquer paints are identical to one another except that the paint in the spray can has propellant mixed in.
This is not a problem accept in certain cases when decanting (which will be addressed below) however the thinning and quality of work when these lacquer paints are airbrushed will be the same.
Factors Affecting Tamiya Lacquer Paint Thinning Ratio
Before we start looking at specific paint thinning ratios there are a few factors you must be aware of that will affect how much you thin your lacquer paint.
This is important as there is no “one size fits all” answer to exactly what thinning ratio you should use, rather it’s an estimate based on what factor listed below are important to you or will impact how you use your airbrush.
What Compressor Air Pressure Will You Use
Air pressure will make a big difference to the quality of your work, all other things being equal.
If you use a higher air pressure you’ll be able to adequately airbrush thicker paint with less thinners in it.
Conversely, if you use a lower air pressure, that same thick paint will potentially spray in a ‘spattering’ way and give a rough finish and may even clog up the nozzle entirely.
This is because there is not sufficient air pressure to make the paint atomise and flow properly.
In this case of using low air pressure you will have to use some amount of thinners to get the paint to a more watery consistency so that it atomises properly.
The higher the pressure, the less thinners required, possibly none at all.
The lower the pressure, the more thinners required.
Are You Airbrushing Fine Detail Or Wide Coverage (nozzle & needle size)
If you want good coverage of paint over a wide area you’ll want to push a lot of paint out of your airbrush in a short amount of time, for example, when top coating a car body.
In this case you’ll want use a larger nozzle and needle size, say 0.35 mm to 0.5 mm, and these nozzle sizes will allow for thicker paint to flow through them successfully.
This means you can possibly airbrush Tamiya lacquers with larger nozzle sizes without thinning as much, or perhaps without thinning at all.
If you need fine detail and thin lines from your airbrush and opt to use a smaller nozzle and needle combination, then you’ll need to thin the paint down more with a higher ratio of lacquer thinners to lacquer paint.
If you don’t thin your Tamiya TS paint sufficiently and use small nozzle and needle sizes you may find that the paint clogs the nozzle and the airbrush becomes unusable.
Additionally, smaller airbrush nozzle and needle sizes typically use a lower air pressure, and as we found in the section above, if you use a lower air pressure you need to thin your paint out more.
So the takeaway is…
The wider the coverage you need, the less thinners required, possibly none at all.
The finer airbrushing detail required, the more thinners you’ll need.
Other Airbrush Considerations…
There are a number of other factors that will contribute to how much you should thin your Tamiya lacquer paint for airbrushing, such as:
- Distance you hold the airbrush from the job (will largely be defined by how much pressure you use though);
- The colour of the paint you use;
- Equipment quality, etc
However the list above aren’t typically things that will be as impactful as the two main factors listed earlier of air pressure and spray coverage requirements.
Be aware of these other factors, but don’t send yourself insane trying to get the absolute perfect thinning ratio for every possible airbrushing scenario.
With a bit of testing and practise you’ll find that you soon land on the best ratio for your own personal setup and needs and can run with that every time regardless of the ‘other’ factors listed above.
So… How Much Thinners Do I Use For Airbrushing Tamiya TS Lacquer Paint?
I’ve seen people all over the net make claims of using no thinners at all in a tiny 0.2 mm nozzle airbrush, to using a 50/50 ratio in a larger 0.5 mm nozzle airbrush.
Just to clarify, that’s essentially the opposite of the conventional wisdom of thinning paints as detailed above.
That’s not to say it didn’t work for these people, but we have no idea what conditions there were spraying in nor do we know the quality of the equipment they were using.
And the reality is that perhaps they didn’t really know what they were talking about either… 🙄
So here’s how you should start out thinning your Tamiya TS lacquer paint…
Use a ratio of 3:1 paint to thinners mix to start with, and do a test spray.
Why do I suggest the above ratio?
- My current airbrush is an Iwata with a 0.5 mm nozzle and it sprays perfectly well with this ratio of thinning, and sometimes I’ll go a little heavier with the thinners to perhaps so 1.5:1 paint to thinners ratio at very low pressures;
- When I’ve tried spraying straight un-thinned Tamiya lacquer out of my 0.5 mm nozzle it doesn’t quite atomise properly and gives me horrendous spray quality;
- It’s a good middle-ground place to start and doesn’t overly thin the paint – remember, you can always add more thinners in, you can’t take thinners out (well you can add paint of course, but that doesn’t help you judge the thinning ratio and it can be messy if you’re decanting again).
You will inevitably come across people who say that you should thin the paint to the consistency of milk.
The reality is that a thinning ratio of Tamiya lacquers of 3:1 will probably be thicker than milk, but this is ok.
We’re starting with a low amount of thinners and working up to test what works for your airbrush setup and airbrushing environment.
What works for one person may not work exactly the same for another, so we’re taking it step by step to begin with.
Test Spray, Then Adjust Your Thinners To Paint Ratio Accordingly
First of all set your compressor at the recommended air pressure setting for your airbrush, and do not change it while you’re test spraying
Then get a stiff piece of card or an old kit you can do a test spray on, and look for the following:
- Does the paint hit the surface and spread in a watery like fashion? If it does this then your paint is too thin. It means you have to discard what’s in your airbrush and start over with straight Tamiya lacquer paint without any thinning. My expectation though, is that it’s very unlikely that you’ll experience this with a thinning ratio of 3:1;
- Does the paint spatter or clog? If it does, then you need to increase the amount of thinners. You can increase the ratio to approximately 2:1 by adding the same amount of thinners you did in the first place and doing this test again. When you do another test spray with the additional thinners, if it still spatters then add more thinners again in the same manner until you get it to spray perfectly.
- Does the paint go on perfectly? Great work, you nailed it! Make sure to take note of how much paint you used originally and how much thinners you ended up needing. Whatever ratio you ended up at is what you’ll work with from now on. From here it’s all fine tuning to get perfection!
The above process works just as well if you’re using a lower pressure with a smaller nozzle and needle size to get better fine lines and detail work with your airbrush.
Go through all the same steps, but you can actually start at the thinning ratio you already discovered for your larger nozzle and needle size.
How do I actually measure the ratio out of thinners to Tamiya paint out?
This is where decanting Tamiya spray paint, or pouring from the jars, directly into a mixing jar is beneficial.
It allows you to visually see the amount of paint you have in the clear jar and add the correct amount of thinners accordingly.
I’ve always eye-balled this measurement and had good results, however you may wish to use a cheap mixing jar with volume markings on it such as Tamiya sells and then measure out the correct amount of thinners to add.
👍 To see reviews and prices of these Tamiya mixing jars click here.
After a little practise at this you’ll get a feel for doing it by eye and can start mixing directly in the airbrush bottle (siphon feed) or cup (gravity feed).
How To Handle Decanted Tamiya TS Spray Paint Propellant Gassing Out
You may notice that decanted Tamiya TS spray paints bubbles and froths to some degree when it’s sprayed into the jar or airbrush cup.
This is the propellant gassing out, and you should let settle down entirely before you start airbrushing.
There are two ways you can speed up the process of gassing out so that you can use the paint almost immediately without detriment:
- Stir the paint gently with a toothpick or paint stirrer of some kind. This may initially make the paint froth up more so if your jar or cup is fairly full don’t be surprised if it spills over. I’ve found that this is very much the case with Tamiya primer that’s been decanted. You simply need to put the toothpick into the paint motionless at first, which may be enough to get a reaction. Then start stirring very slowly, increasing the speed so that you don’t have any froth up and spill over. Very quickly the propellant should finish gassing out.
- Put some thinners into the paint. You’ll be doing this anyway so you can potentially skip the above step with the toothpick. Just applying a few drops of thinners tends to make the bubbling settle down very quickly. Just make sure you’re aware of how much you’re putting in to get your thinning ratio correct.
Some modelers will suggest that you leave the paint for some hours or overnight before using it, but I’ve never found that I had to do this and have always achieved great results using the methods above.
As always, test, test and test some more.
Going through the testing process can make us impatient as we just want to get on with building awesome models that we can post online for internet glory, but spending a short while doing some initial testing will serve you exceptionally well in the long run and give you better results moving forward. 👍