Winterdyne
1st Apr 09, 5:01 AM
Thought I'd donate a little airbrush tutorial, in an effort to improve my writing. :-) I hope this is found helpful.
[NOTE] This is a work in progress. This first post will be updated periodically.
Please feel free to ask questions, point out anything I'm doing heinously wrong etc...
----------------------------------------------------
Airbrush 101 - Part One - Equipment.
This part of the tutorial is aimed specifically at those completely new to the idea of airbrushing, particularly using a dual-action airbrush. I'm being quite specific with the kit I use, although most people will probably have quite a similar setup.
The key to successful airbrushing is preparation, and knowing your kit. Here's what I have on my desk before starting an airbrushing session:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig1.jpg
1: Airbrush holder. Firmly blu-taked to the table. This is essential to put your airbrush on without spilling paint from it.
2: Drops tray. For emptying the cup of the airbrush before carrying it over to the sink to rinse it out. Also for dumping q-tips used in cleaning and other general crap you don't want lying around.
3: Airbrushes. I currently use a Revell DB-750 profi-plus draw feed dual action and a cheap AB-130 gravity feed dual action from EverythingAirbrush (an absolute bargain, and a lovely brush, which I'll be using in the tutorial).
4: A wet pallete. Used to hold paint I'll apply by brush at points. Helpful in judging mixes to use.
5: 1ml syringes and a pipette. The syringes are used for handling paint, and the pipette purely for thinners and water.
6: The models in question. Having them in front of you helps you plan. In this case we have a rhino I've just preshaded, and one which still needs the treatment.
Familiarity with your equipment and how it works is important, too. Here's the AB-130 in more detail. It has many features in common with other more expensive dual-action gravity feed brushes:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig2.jpg
1: Needle cap. Internal mix airbrushes (ones that mix the air and paint inside the body of the brush) work by drawing the paint along a needle to the nozzle. This cap covers the needle and can be removed for very close work. It is important not to damage the end of the needle as this can lead to spatter.
2: Paint cup. In gravity-feed brushes like this, the paint is stored in a chamber also containing the needle, and gravity pushes it down. Also, with the cup being above the body of the brush it's easier to add paint to it on the fly (ie whilst there's still another colour in it), which is very useful in preshading and blending techniques. The mix of paint is important - you need to use very thin paint (about 4 : 1 thinner : paint at minimum), as is the choice of thinner - for close work a quick-drying medium will help avoid runs and too 'wet' an application, at range water is ok, as is a future/klear and water mix.
3: Trigger. Push it down to make air flow through the brush and pull it back to draw back the needle, allowing more paint to flow through the nozzle. The technique is to get air to flow first (point away from your work to throw off any spatter) then point at your work, let the air flow first and then gently pull back to increase the paint flow. More pressure down on the trigger allows more air to flow, as does having a higher output pressure set on your compressor (see later).
In general:
High pressure + high paint flow = large spray pattern, best at distance, with slow-drying paint (water medium rather than iso-alcohol (eg Tamiya).
Low pressure + low paint flow = very small spray pattern, best at very close range with a quicker drying medium (alcohol based).
4: Air inlet. This is where the hose from the air source connects to the airbrush. Be aware that you'll have a dangling pipe under your hand that can potentially catch on things.
5: Action limiter. This is a screw-stop that prevents the trigger from being pulled back more than a certain distance, and is useful for limiting the spray to a small area.
Okay, now we need to talk about air sources. Give up the propellant cannisters - they're expensive. I use a machine-shop compressor. It's loud, but has a big tank. You can find smaller, quieter compressors, but you'll also find an increasing price in line with the convenience. There are a few extra things you need too:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig3.jpg
1: Output regulator. You don't want your pressure to be reliant on what's in the compressor (or it'll be running all the time, loudly). This controls the flow of air into the hoses for the brushes and closes when the required pressure is reached. For most purposes, you'll be wanting a pretty low pressure - I use around 15-20 psi. For varnishing and large area work, crank it up to around 25.
2: Isolator. You want to be able to stop the flow of air to the hoses so you can disconnect brushes to clean them without venting the tank.
3: Moisture trap. When you have air under pressure escaping, it's cold, and this causes any water vapour in it to become liquid quite easily. Obviously this will effectively add water to your paint. This little chamber catches any condensate coming out of the compressor.
4: Pressure release valve. On the other side of the isolator, this allows you to remove the pressure from the hoses, allowing you to disconnect your brushes without escaping air causing the hoses to buck.
5: 1/16" nipple. For small (badger standard) airbrush hoses. In general you'll need one of these to connect your airbrush to a standard compressor.
6: 1/8" nipple. For larger airbrush hoses. The fun I had finding one of these locally after forgetting to order it along with my airbrush...
Now, getting ready to start - we have our airbrushes in the holder...:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig4.jpg
... and importantly, the hoses are not tangled - you don't want to be pulling the other brush around while painting (especially if it has paint in it!):
http://www.winterdyne.co.uk/maz/images/airbrush101/fig5.jpg
Coming up in part 2 (should be later today), we'll take this flat DA green Rhino:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig6.jpg
And turn it into something looking like this, ready for detailing, metallics and weathering:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig7.jpg
End of Part 1.
Part 2 - Preshade Airbrush Work
We start by putting some water into the cup:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig8.jpg
Then a few drops of flat black paint:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig9.jpg
We mix it up with a paintbrush, should look something like this:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig10.jpg
Test the consistency on a piece of paper with both the brush...:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig11.jpg
... and the airbrush. ALWAYS test spray before each pass on the paper, not the model. This avoids unexpected spatter, and helps you get a good feel for the spray pattern you want. In this case, we want a pattern that's about 4-5mm across, and fairly translucent:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig12.jpg
We spray the black over all raised edges (where you'd think of putting an edge highlight) and into deep recesses. Spots are sprayed onto individual rivets that we want to define sharply.
Don't worry too much about neatness, as the filter and highlight coats will tidy things up. This said, you do not want runs (dribbly paint) to occur, so make use of the practice paper before you point the brush at the model to get a feel for the distance you need to hold. The effect you want is for the paint to go on looking moist, but to appear to dry almost immediately in the airflow. I took around 15 minutes to get to this stage.
This will look very harsh at this stage, but it will be toned down:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig13.jpg
Clean out the brush, and this time put DA green into the water. Mix it up with a paint brush...:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig14.jpg
...check the consistency...:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig15.jpg
...and test spray. We want a slightly larger spray pattern this time. Again we want to have a feel for the correct distance to avoid runs:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig16.jpg
We apply a gentle filter coat from high angles (down towards the model, with the model upright) and also concentrate on the centres of large panels to brighten them. Large areas naturally reflect more light than small, so the observer's brain expects them to be brighter. This gives a small model the impression of being bigger:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig17.jpg
We repeat this process a couple of times, each time adding a little Snot Green to the mix along with a few drops more water:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig18.jpg
Here you can see the consitency check for the third time - note that by putting a test stroke on the white paper we can immediately see if the mix is a brighter green:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig19.jpg
After the two highlighting passes (taking maybe 20 minutes), with the airbrush we have this:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig20.jpg
All that remains now is a light drybrush with Snot Green on the edges and rivets and to paint the metalwork black.
End of Part 2.
[NOTE] This is a work in progress. This first post will be updated periodically.
Please feel free to ask questions, point out anything I'm doing heinously wrong etc...
----------------------------------------------------
Airbrush 101 - Part One - Equipment.
This part of the tutorial is aimed specifically at those completely new to the idea of airbrushing, particularly using a dual-action airbrush. I'm being quite specific with the kit I use, although most people will probably have quite a similar setup.
The key to successful airbrushing is preparation, and knowing your kit. Here's what I have on my desk before starting an airbrushing session:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig1.jpg
1: Airbrush holder. Firmly blu-taked to the table. This is essential to put your airbrush on without spilling paint from it.
2: Drops tray. For emptying the cup of the airbrush before carrying it over to the sink to rinse it out. Also for dumping q-tips used in cleaning and other general crap you don't want lying around.
3: Airbrushes. I currently use a Revell DB-750 profi-plus draw feed dual action and a cheap AB-130 gravity feed dual action from EverythingAirbrush (an absolute bargain, and a lovely brush, which I'll be using in the tutorial).
4: A wet pallete. Used to hold paint I'll apply by brush at points. Helpful in judging mixes to use.
5: 1ml syringes and a pipette. The syringes are used for handling paint, and the pipette purely for thinners and water.
6: The models in question. Having them in front of you helps you plan. In this case we have a rhino I've just preshaded, and one which still needs the treatment.
Familiarity with your equipment and how it works is important, too. Here's the AB-130 in more detail. It has many features in common with other more expensive dual-action gravity feed brushes:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig2.jpg
1: Needle cap. Internal mix airbrushes (ones that mix the air and paint inside the body of the brush) work by drawing the paint along a needle to the nozzle. This cap covers the needle and can be removed for very close work. It is important not to damage the end of the needle as this can lead to spatter.
2: Paint cup. In gravity-feed brushes like this, the paint is stored in a chamber also containing the needle, and gravity pushes it down. Also, with the cup being above the body of the brush it's easier to add paint to it on the fly (ie whilst there's still another colour in it), which is very useful in preshading and blending techniques. The mix of paint is important - you need to use very thin paint (about 4 : 1 thinner : paint at minimum), as is the choice of thinner - for close work a quick-drying medium will help avoid runs and too 'wet' an application, at range water is ok, as is a future/klear and water mix.
3: Trigger. Push it down to make air flow through the brush and pull it back to draw back the needle, allowing more paint to flow through the nozzle. The technique is to get air to flow first (point away from your work to throw off any spatter) then point at your work, let the air flow first and then gently pull back to increase the paint flow. More pressure down on the trigger allows more air to flow, as does having a higher output pressure set on your compressor (see later).
In general:
High pressure + high paint flow = large spray pattern, best at distance, with slow-drying paint (water medium rather than iso-alcohol (eg Tamiya).
Low pressure + low paint flow = very small spray pattern, best at very close range with a quicker drying medium (alcohol based).
4: Air inlet. This is where the hose from the air source connects to the airbrush. Be aware that you'll have a dangling pipe under your hand that can potentially catch on things.
5: Action limiter. This is a screw-stop that prevents the trigger from being pulled back more than a certain distance, and is useful for limiting the spray to a small area.
Okay, now we need to talk about air sources. Give up the propellant cannisters - they're expensive. I use a machine-shop compressor. It's loud, but has a big tank. You can find smaller, quieter compressors, but you'll also find an increasing price in line with the convenience. There are a few extra things you need too:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig3.jpg
1: Output regulator. You don't want your pressure to be reliant on what's in the compressor (or it'll be running all the time, loudly). This controls the flow of air into the hoses for the brushes and closes when the required pressure is reached. For most purposes, you'll be wanting a pretty low pressure - I use around 15-20 psi. For varnishing and large area work, crank it up to around 25.
2: Isolator. You want to be able to stop the flow of air to the hoses so you can disconnect brushes to clean them without venting the tank.
3: Moisture trap. When you have air under pressure escaping, it's cold, and this causes any water vapour in it to become liquid quite easily. Obviously this will effectively add water to your paint. This little chamber catches any condensate coming out of the compressor.
4: Pressure release valve. On the other side of the isolator, this allows you to remove the pressure from the hoses, allowing you to disconnect your brushes without escaping air causing the hoses to buck.
5: 1/16" nipple. For small (badger standard) airbrush hoses. In general you'll need one of these to connect your airbrush to a standard compressor.
6: 1/8" nipple. For larger airbrush hoses. The fun I had finding one of these locally after forgetting to order it along with my airbrush...
Now, getting ready to start - we have our airbrushes in the holder...:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig4.jpg
... and importantly, the hoses are not tangled - you don't want to be pulling the other brush around while painting (especially if it has paint in it!):
http://www.winterdyne.co.uk/maz/images/airbrush101/fig5.jpg
Coming up in part 2 (should be later today), we'll take this flat DA green Rhino:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig6.jpg
And turn it into something looking like this, ready for detailing, metallics and weathering:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig7.jpg
End of Part 1.
Part 2 - Preshade Airbrush Work
We start by putting some water into the cup:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig8.jpg
Then a few drops of flat black paint:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig9.jpg
We mix it up with a paintbrush, should look something like this:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig10.jpg
Test the consistency on a piece of paper with both the brush...:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig11.jpg
... and the airbrush. ALWAYS test spray before each pass on the paper, not the model. This avoids unexpected spatter, and helps you get a good feel for the spray pattern you want. In this case, we want a pattern that's about 4-5mm across, and fairly translucent:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig12.jpg
We spray the black over all raised edges (where you'd think of putting an edge highlight) and into deep recesses. Spots are sprayed onto individual rivets that we want to define sharply.
Don't worry too much about neatness, as the filter and highlight coats will tidy things up. This said, you do not want runs (dribbly paint) to occur, so make use of the practice paper before you point the brush at the model to get a feel for the distance you need to hold. The effect you want is for the paint to go on looking moist, but to appear to dry almost immediately in the airflow. I took around 15 minutes to get to this stage.
This will look very harsh at this stage, but it will be toned down:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig13.jpg
Clean out the brush, and this time put DA green into the water. Mix it up with a paint brush...:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig14.jpg
...check the consistency...:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig15.jpg
...and test spray. We want a slightly larger spray pattern this time. Again we want to have a feel for the correct distance to avoid runs:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig16.jpg
We apply a gentle filter coat from high angles (down towards the model, with the model upright) and also concentrate on the centres of large panels to brighten them. Large areas naturally reflect more light than small, so the observer's brain expects them to be brighter. This gives a small model the impression of being bigger:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig17.jpg
We repeat this process a couple of times, each time adding a little Snot Green to the mix along with a few drops more water:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig18.jpg
Here you can see the consitency check for the third time - note that by putting a test stroke on the white paper we can immediately see if the mix is a brighter green:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig19.jpg
After the two highlighting passes (taking maybe 20 minutes), with the airbrush we have this:
http://www.winterdyne.co.uk/maz/images/airbrush101/fig20.jpg
All that remains now is a light drybrush with Snot Green on the edges and rivets and to paint the metalwork black.
End of Part 2.