Airbrushing!!! "Everything you wanted to know but were afraid to ask"

[Guest]

First of all lets clear up one thing!! An Airbrush will not improve your models, infact it will make them look worse! Only once you have got the basics right can an airbrush help you to improve! I suggest people view Bunkerbarges " Back to basics" before you even think about using an airbrush! That being said an Airbrush can make a model come to life. It can convey a sense of depth detail and finesse that no brush can compete with!

So lets examine what an airbrush is. As stated its not the be all and end all! Its a tool to help you acheive results that can be incredibly realistic or it can highlight every flaw on your model. An airbrush is simple its a brush that uses air to put paint on a surface !!!!! Im afraid though its not that straightforward.

A popular misconception is that an airbrush is an airbrush is an airbrush!! This is not so. Airbrushes come in two types "single action" and "double action" Cheaper alternatives are actually spray guns or atomisers! i will try to explain the difference.

An Atomiser or spraygun works by blowing air across a opening creating a vacume that lifts the paint up into the airflow producing a spray. See badger 350 paasche vlr humbrol and so on. Humbrol revell also sell a rebadged badger 200 which are single action airbrushes

Single action Airbrushes use a needle that is operated seperately from the trigger Ie a knurled screw that is at the back of the airbrush this arrangement allows the needle position to be determined by turning it in or out " in for a finer spray out for a broader coverage" Whilst the trigger controls the airflow. Whilst superb results can be obtained from this type of brush , it does not give you the finnesse and control that a double action can.

Double action ie devilbiss sprite, iawata , aztec, badger 150 etc, paasche vjr. Give you total control of both airflow and paint flow from the trigger. Pull the trigger back increases the paint flow ! Push the trigger down increases the airflow! This then gives you unlimited control of the pattern you want to use from 1/64 fine line to about 1/4 inch broad pattern.

I at this time own a Iawata A badger 200. A devilbiss 63, A paasche vjr. All have their pros and cons but despite the Iawata being twice the price of the Paasche this is my choice of use when it comes to fine detail work. What im trying to say is that an airbrush is very much an extension of you they are what you make of them and practice practice practice is the order of the day.

The next installment will deal with paint types, flow qualities, and propulsion.

[Guest]

thanks nige, that has answered some of my doubts as to the different types,

could you gives us rough ideas of which type you would use for different jobs ?

do different type of brushes react differently to different paints etc .

i hope i`m not jumping the gun

Adz..

[wonwinglo]

Keep it going Nigel,you really know your airbrushes for sure,looking forward to the next installment.

[Guest]

I knew this was going to be interesting!

Nigel, much appreciated, I look forward to the rest.

[Guest]

Nigel,

From what you are saying would it be fair advice to offer that modellers should get to grips with a single action unit before going to the obviously additional expense of a double action brush or can double action brushes be used in a single action manner from the start.

I can't even comprehend at the moment trying to control paint flow and air pressure at the same time. I spend all my time trying to ensure that the brush is at the correct angle and distance from the job!

[Guest]

Nigel,

can you also give us a breakdown of what equipment is required and rough price ranges for the beginner?

Thanks

[Guest]

More

Trying to deal with some of the queries raised

Single or double ??? A good double action should have a adjuster nut , wheel or screw that can be used to make the brush perform as a single action design the adjuster will push the trigger back to the desired point and all you will have to control would be the airflow!

The main drawback on some single actions is that they come with a jar receptacle rather than a paint cup. This gets in the way when you want to do fine freehand work.

as regards mediums i always use enamels not because they are better its because thats what i understand best they are what im happy using and i know the characteristics of flow dry time and coverage!

The most important thing is airflow or a compressor!!!! Please please please dont skimp on this a good silent type i.e fridge type of unit will give you many years of service and will pay for itself many times over The most important aspect of it is that unlike the diaphram kind you wont get the domestic authorities complaining about the racket! Seriously though a cheap compressor will be a mistake if it hasnt got a resevior for the air the supply will pulse!! resulting in uneven lines (almost a dot every couple of mills) A moisture trap is also essential as compressed air is hot and this holds moisture which will spatter on your paint finish causing you much annoyance and expletives. A good moisture trap will also incorporate a pressure regulator which helps no end in being able to spray a variety of consistencies and finishes. Propellent bottles are way too expensive !! You will be using 2 or three per model the costs soon adds up! you can also get a co2 tank but this to me brings other inconvieniences such as refilling etc Hope this helps a bit

[Guest]

Nigel,

I think the biggest problem with disposable bottles, which is why I would always advise against them, is the fact that as the gas evaporates the temperature of the remaining liquid falls. This is due to an overall reduction in energy of the contents as the higher energy molecules (the gas) are removed from the bottle.

Anyway the result is that as the gas is used and the temperature drops the rate of evaporation reduces and consequently the pressure of the saturated vapour drops. The big problem is therefore that the pressure of these things is not a constant and it throws out any carefull airbrushing operation completely.

A compressor is the only way to go, bearing in mind the considerations that you point out.

[wonwinglo]

I once had a huge lorry inner tube wedged between my two sheds,with an adaptor it provided convenient but somewhat bulky pressure for my older Humbrol Studio airbrush.

Those cannisters are not very successful and as you say kick out water all the time.

Question for Nigel ? can I fit a pressure gauge and water trap between my Diaphragm compressor and the airbrush ? I have got away with it up until now but would like to at least fit the water trap,do they make a simple one that fits in the line ? those lines are so narrow.

[Guest]

Guys,

These people are suppliers of all things air brush and can help with most requirements.

www.graphicair.co.uk

and

www.widespreadsolutions.co.uk

(They're in Yorkshire as well so they must be OK!!)

[Guest]

Barry yes you can you can get a pressure reg with a watertrap that fits the standard compressor thread (its also a standard badger size ) so that will make life easier! If you have a diaprham type the regulator will go most ways to reduce the pulsing effect just make sure you dont use more than 15 psi as the badger hose is way to thin really. it can come loose from the airbrush after a few uses

[Guest]

Richard the VJR you won has the facility to be used as a single action though it is a fine detail brush so dont be surprised if you dont get wide coverage

[wonwinglo]

*** Thanks Nigel,very useful,I will look out for one.

Barry yes you can you can get a pressure reg with a watertrap that fits the standard compressor thread (its also a standard badger size ) so that will make life easier! If you have a diaprham type the regulator will go most ways to reduce the pulsing effect just make sure you dont use more than 15 psi as the badger hose is way to thin really. it can come loose from the airbrush after a few uses

[Guest]

Whilst I would in no way advise as well as Nigel, here are a few thoughts on my set-up.

I use the Paashe VLS and diaphram compressor that came with it. This is really noisey but is fitted with the regulator/trap and I normally use it in a box about 2x1x1 feet with pull down lid. I also use a "lazy susan" turntable to allow for easy maipulation of the small workpieces.

Let me say right away that all my experience is with single colour coverings, nothing like the weathering effects Nigel talks about.

The pulsing effect , even through the regulator, is still present but can be nullified by using an extention air-line, I use a 20 foot job.

The regulator, together with the double action brush, does allow for the spraying of very small pieces without blowing them away. I always attempt to fit 1/8in dowel as "locators" to these pieces and fit them into pre drilled holes in a baseboard used only for spraying. Pieces too small to take dowel are held down with a blob of plasticine though this is not always succesful, some are blown away no matter how careful I am, more practice needed there.

[Guest]

Richard people generally put the propellant bottles into warm water to avoid this problem (it works up to a pont)