Decanting Paint my Way

i will start this one as simple as i can….

I AM CHEAP!!

ok now that being said, i cant stand the cost of paint. for what it is, the prices can add up very quickly for a multi color finish or even the basic stock one color job.

the average car modeler buys the 3oz cans of both primer and paint
the going prices of these equate to a single paint job running between 12 and 18 dollars depending on where you buy and the brand you buy.

with the unregulated air pressure and oversized spray nozzles you can expect to get 2 cars worth of primer from a 30z can and 1 5 coat finish ( 2 mist coats and 3 wet) from the color

i dont think that is good enough or cost effective, so i decant everything into different bottles and shoot them through my airbrush.

with that same amount of paint in the cans, i can get 6 cars worth of primer and enough paint to cover 3 cars. all this because the airbrush allows you to control paint flow and air pressure so there is less wasted product and you are laying down thinner coats of paint.

i always get the same questions any time i try to explain this to anyone.

arent you afraid the can will explode?
doesnt it make a mess?
why should i bother when i can just use the can?
no i am not afraid the can will explode because i make sure that cant happen, no it doesnt make a mess when done properly, unless you have more money than sense there is no reason not to decant your paints, it makes the same amount of product go roughly 3 times further, many times with better results.

first i grab a can of primer for this demonstration
i bought this one for 6.99 plus tax from autozone. its a 12 oz can but the process is the same for the 3oz hobby size.

if you think of how a can of spraypaint is manufactured, it is easy to understand why this works.

as you can see, the dip tube extends to the bottom of the can and the propellant settles at the top.

when you invert the can…

the propellant is exposed to the dip tube and can be expelled without losing any of the paint.

keeping the can inverted, depress the nozzle until all the propellant is expelled.
dont be fooled here, the propellant is a gas and it saturates the paint. once it stops spraying because of no pressure, stop depressing the nozzle, shake the can for 10 seconds, flip the can again and depress the nozzle again. you will be surprised at how much additional pressure builds up in that time. repeat this step 3 or 4 times until it no longer builds pressure.

the propellant is now expelled and it is safe to “open” the can.

i use a nail for this next step because i am kinda neanderthalish lol

it is easiest to use the seam of the can as a target here, as you can puncture the can both top and bottom on the same side of the can.

the hole near the bottom of the can is where the paint will stream out of when we are done

the hole at the top is to allow air into the can which lets the paint flow out in a stream rather than gurgling.

once you have your 2 holes, it is a simple matter of finding an acceptable container to store your paint in.

i am partial to these

you can find them either on the internet or even restaurant supply stores. most come with a plastic clip on cap so you dont have to worry about your paint evaporating and the squeeze bottle design is ideal for filling paint cups on air brushes with no waste.

now all thats left is to use a small clean funnel (i have one i use for this purpose alone ) and pour your paint from the can into the bottle.
clean out your funnel as soon as you are done so it is ready for your next one.

thats all there is to it, you now have a squeeze bottle of your paint you can fill your airbrush with and saved yourself some money in the process.

even with the cost of the squeeze bottles ( currently under 3 dollars for a 6pack) you have more than doubled the usefulness of your paint without wasting any product.

Paint Lifting

This week i ran into a problem i have had numerous times before.

paint lifting.

what is paint lifting?

paint lifting is what happens when you try to cover a cool paint with a hotter paint.

the terms hot and cool are based on their carrier fluids

acrylic= water or rubbing alcohol = cool

enamel= mineral spirits = warm

lacquers/acrylic enamel/acrylic lacquer = lacquer thinner/ acetone = hot

you can spray cooler paints over hot ones without a problem 100% of the time.

also conventional acrylics can be overcoated with anything once they dry fully.

the problem i had was actually because i didnt do research and assumed Tamiya acrylics were like others i have used.

the long and short of it was i laid a base coat of tamiya aluminum on a P-51 i am building and then went to clear coat it with duplicolor clear.

the base coat …

 

 

i then decided to clear the kit after it had sit to dry for a few days

i grabbed a can of duplicolor clear and decanted some into the airbrush

3 light coats and everything looked good for a couple minutes, then the chemical reaction started.

 

 

 

now any other true acrylic on the market would not have done this. Tamiya’s acrylic is a modified acrylic ( dilutes with rubbing alcohol/ water but is in truth solvent based. because that solvent was colder than the solvent in the duplicolor, the solvent attacked the basecoat and started to lift or crinkle it in a few assorted areas.

some areas will be sanded and repainted, others will get a bath in purple power down to bare plastic and then redone.

live and learn.. or in this case.. i live and you learn from it =o)

What kind of airbrush do you need?

this is more of a universal answer to question’s i see at the very least, a couple times a week in different forums or facebook.

the question’s are normally something like these…

i have been using a rattle can all my life and want to try an airbrush, whats the best kind?
whats better, a spray can or an air brush?
i have never used an airbrush before, should i buy the newest $200 one?

now, i am going to cover as much as i can about air brushes in this post, i will break it down into categories

Q:Why is an airbrush better than a rattle can?

A:The biggest advantage to an airbrush is the price…. yes you read that right. While you have the initial cost of investment when you first buy your airbrush, over time it easily pays for itself. Say the average hobby sized 3oz rattle can, a quick google search tells me they retail at between 4 and 6 dollars each can. when using straight from the can, a basic 2 mist coats and 2 wet coats paint job, you can expect 1 1/25- 1/25 scale coverage with a bit left over. Now, decant that same 3 oz into a bottle and shoot it through an airbrush, using the same sequence, and you will use the same amount of paint to spray 3 kits instead of 1. you just saved yourself the cost of 2 cans of paint on your first paint job. This is because that by default, the size of the tip on the rattle can is too large, allowing way more paint than needed to leave the can, the air source is also unregulated on the rattle can, this means that the more the can is used, the less the pressure propelling the paint, by using an air brush, you control both of these variables and con optimize them.
The second reason behind the cost factor is the fact that [b]you are not restricted to just hobby paints[/b] for your paint jobs any more. You can shoot any paint medium you like through the airbrush as long as it is thinned properly. one popular thing to spray through an airbrush is nail polish. nail polish is only very thick lacquer paint. if thinned properly, down to the correct consistency, it makes a long lasting, durable and brilliant model car paint. Nail polish comes in many more colors than even the most extensive line of model car paints. I buy mine from a local flea market here for $1 a bottle, i get a deal of $5 if i buy six of them at the same time. Through an airbrush , after thinning( i currently thin nail polish with medium temp lacquer reducer bought from the local car parts store ), i can shoot a whole kit with one 1/2 oz bottle of nail polish . that equates to 83 cents a paint job, try to do that with hobby paint.
Airbrushes are also great for interiors, since alot of interiors are flat, rather than glossy, one of the best things i have found to shoot them with is craft paint, currently i use apple barrel brand craft paint which i get at wallmart for 60 cents for a 2oz bottle. when shot through an airbrush, there are no brush strokes, you get a nice clean uniform finish. start with the background color, and then use a normal brush later to pick out the details.

Another advantage to an airbrush over a rattle can is control. even the most simple air brushes have controls on them to not only regulate paint flow and air pressure, but also the size of the spray pattern coming out of them. this allows you to use the airbrush in places where a rattle can is just not viable. i will use my 62 bel air as an example.

if you look at the pic above you can see a pattern in the side panel inlays, this was a detail i decided to add because it adds interest to the eye instead of just a basic one color inlay. this was done easily with a piece of paper and the air brush, you would not be able to do the same thing with a rattle can because it lacks the control of the spray pattern.

Q: which type os airbrush is best, single action or double action, also whats better, internal mix or external mix?

A: it really does not matter. i know i will take flack for this answer from some of the aficionados, but in all truth none of those make a difference in the performance or ability to lay down a stunning paint job.
Lets break them down and explain a bit further…..
By definition:
A single action airbrush delivers both paint and air at the same time when you depress the trigger
A double action airbrush delivers air when the trigger is depressed and will not start delivering paint until the trigger is pulled back.
An external mix airbrush is exactly what it says, the paint never actually travels through the airbrush itself, the siphon tip is located at the nose of the airbrush directly in the air stream. as air passes over the opening in the tip it causes a vacuum which draws the paint up from the jar into the air and then propels it onto the model.
An internal mix airbrush draws the paint into the body of the airbrush itself where it is then shot through the tip and onto the model.
Aribrushes come in four combinations single action external mix, single action internal mix, double action external mix and single action internal mix.

some example pics are below

first is a basic Badger single action external mix airbrush

next is an example of a double action generic airbrush controls

This is a flowchart on how an Internal mix airbrush works

and a Flowchart on how an external mix airbrush works

every type of airbrush is capable of laying down show quality paint. no exceptions.
there is a stipulation though… we will come to that shortly.

Q: should i go out and buy the most expensive airbrush available and expect fantastic results right out of the box?

A: in a word…. NO
some day i am going to get people to listen when i tell them that it is not the airbrush that controls the quality of a paint job, it is the person who is holding the airbrush and their ability to learn it.
let me explain,,, i can go to harbor freight and pick up one of their 15 dollar airbrushes, come home, unwrap it, load it with paint, and start spraying that kit i have been working on for weeks with bodywork getting everything just right. only to have the paint job turn out like crap. i could then blame the airbrush for being “cheap” toss it in the trash and go buy a more expensive one. get home and go through it all again only to have another bad paint job. this is the normal cycle with people new to air brushing. by the time they get to an airbrush that lays paint smooth right out of the box, its not the airbrush that made the difference, its the time they have had holding different ones in their hand which amounts to “practice”.
now if i take that same 15 dollar budget airbrush and take 2 or 3 days practicing with it, learning the air pressures it likes to work with, learning the spray patterns, and the thickness of paint it likes. Once i know that airbrush inside and out, i can lay glass smooth paint with it, bar none. i have been telling people for years that the airbrush itself does not dictate the quality of the finish, its the person that holds it with experience that can do wonders with them.
now do not get me wrong, there are reasons to upgrade to the more expensive airbrushes. the 15 dollar ones are normally constructed with cheaper parts, often times plastic bits that wear out fairly quickly. when you move up the scale a bit you find those parts are then made of metal and tend to last longer. But that is the only reason to upgrade that i can think of. it is quite possible that you can get 2 years out of that cheap one as long as it is taken care of properly.

My recommendation?

If i were just getting into airbrushing myself and had to decide on a good all around airbrush…
i would buy a testors Aztek airbrush, i have owned one before and i actually loved it, it is capable of being both single action or double action, comes with a 2 year warranty, has interchangeable tips ( fine medium and a high flow which is great for bodies when you are shooting flakes and pearls) , replacement tips are cheap and easily found, can use both color cups and paint jars, very easy to clean and maintain,they are not the cheapest out there by far, ( just found a few on ebay for the $60 range) but they are an excellent all around airbrush.
In all actuality, it will probably be my next airbrush purchase.
in a nutshell, if you are just getting into the world of airbrushing, dont “waste” your money on a top of the line airbrush costing hundreds of dollars, you can upgrade to one of them at a later point, after you learn to use one. the key to learning an airbrush is the same as with anything else… you need to have patience. i have seen many a different modeler pick up even a moderately expensive airbrush setup, only to see it a week later on ebay because it ” didnt work” for them. taking the time to learn your equipment is the biggest benefit you can give yourself.

good luck and if i can answer any questions you might have, let me know

**Update**
OK it has been a while since i wrote this so i figure i would add a bit more to it.
Couple years ago, after i wrote this article, the wife surprised me with an Aztek airbrush for Christmas. it was exactly as i remembered it and a great all around airbrush…..i now own the Aztek, an Iwata Neo, an Iwata Eclipse, a Paasche Vl and 3 other knock off airbrushes from ebay. they all work and they all do what they are supposed to do ( as long as you keep them clean )

Paintology – Part 2 – the Products

Now its time to talk a little bit about paint.

i will try to go into as much detail as possible without being confusing.

the 4 major types of paint i will cover here are as follows:

• Enamel
• Lacquer
• Acrylic
• Urethane

Also, i will add this earlier, rather than later, the acrylic i will be talking about is the water based paints we have available. some manufacturers have taken to calling certain paints ” acrylic enamel or acrylic lacquer” these are not acrylic paints but rather names put on to sell more product when the world is looking for greener painting methods. while there are different things added to each of these 2 sub classes they are nothing more than modified versions of the regular enamels or lacquers and should be treated the same as either.

Starting with the long standby for many modelers, Enamel Paints

By definition, Enamel Paint is: an oil based paint that air dries to a hard, usually glossy, finish.

When applied properly and allowed to cure fully, good ole fashioned enamel paint is resilient, durable and capable of holding up to frequent handling. enamel paints are available in many different forms such as aerosol cans, small bottles and even small tins ( humbrol ).

I have always considered enamel paint to be a slow finish because of the drying time required for the carrier to gas out and harden the paint. In humid areas it can take over a week for the paint to cure hard enough to polish it out. you can cut this time down dramatically with the use of a dehydrator to help “bake” the finish. Enamel paints also have a tendency to go on thicker than some of the other finishes, without proper prep, this can lead to a problem of losing some of the fine details after multiple coats are applied.

As enamels dry they cure by a chemical reaction called polymerization which means the smaller molecules of paint fuse together to form larger molecules as the carrier evaporates.

There is a “recoat” window with enamel paints, this is a “safe time window” in which subsequent coats can be applied without effecting the previous coats. with most enamel you have a 1-2 hour window to recoat, if you miss this window then you will have to wait 5-7 ( longer in humid areas ) days for the finish to cure before applying more coats or your finish may lift and you will have to start over.

Enamel paints can be thinned with either mineral spirits or “paint thinner” . because the dilutent is not considered a “hot” solvent, you can use enamel paints safely over the top of most other finishes without the risk of lifting the underlying finish.

I have also seen many modelers using enamel paint over bare plastic itself without any ill effects of etching the plastic, although this is not something i do myself as i always prefer to prime anything i paint, it is your prerogative.

Now, on to what a Lacquer Paint is: a durable finish that cures strictly by evaporation of the carrier. there is no polymerization process so they dry quicker than enamels.

Another benefit of lacquer paint is that it goes on thinner than enamels, since there is no chemical reaction joining particles together and forming larger ones, you can apply multiple coats and still not obscure fine details which would be buried under a similar treatment with enamel. There is also no limit on the recoat window on lacquer, you can recoat any time you like.

Lacquer paints are thinned with either lacquer thinner, acetone or automotive grade reducer. all three are considered “hot” solvents. This means you cannot use lacquer finishes over a previous enamel paint job as it will lift the paint and destroy the finish. this also applies to enamel primers, hence why i always prime my builds with lacquer primers.

It is not advisable to use lacquer paint on bare plastic, the solvents will etch the plastic giving it a rough bumpy dull finish. and once again do not spray lacquer paint over enamel primer, it wont work out for you.

Acrylic Paints are water based, they have pigment, the carrier is water with extra additives added to cut down surface tension, make the paint flow better, give more gloss and also adhesion promoters.

Companies like tamiya, and createx have an outstanding array of colors for the hobby but once you learn how to reduce things properly you are not just restricted to them. look in your local department or hobby store and you are sure to find an acrylic paint display in the craft aisle. These lend themselves extremely well to brush painting right out of the bottle but can also be thinned and shot through an airbrush without much hassle at all.

because the dilutent is water there are no harsh chemicals or solvents, this makes it safe to spray acrylic paint over any type of finish you like. There is no recoat window so you can respray any time you like. Acrylic paints can also be overcoated with any other type of paint once they are cured fully.

Acrylic is the only paint you can safely paint over bare plastic with no worry of it etching the parts you are painting but it still provides a better finish if they are primed first.

Urethane Paint otherwise known as 2k or two pack paint is directly from the car industry.Urethane paint works by way of a catalyst or hardener. the hardener starts a chain reaction that starts curing the paint and hardening it as soon as it is mixed. You can get single stage urethane paint ( goes on glossy ) or you can do as many do and go with a base/clear system where you lay down your color coats first then when you have the desired hue, bury it under Urethane clear for the glossy shine.

Urethane paints clean up with automotive paint reducer or lacquer thinner. because of the harsh solvents, it is not a good idea to paint it over the top of enamel and i would avoid spraying on bare plastic because it can still etch it.

do not try to save any urethane paint if you have added the hardener, mix only what you think you will need to avoid waste. once the hardener is added, thats all she wrote. dispose of any excess when painting is done and clean your equipment as soon as you are finished, it is near impossible to clean it thoroughly if you let it dry.

A brief word on safety when spraying all but acrylic paints.  

Make sure you spray with adequate ventilation, if you are not spraying in a large, wide open area then you need a spray booth. there are plans all over the internet for making budget spray booths so there is really no reason not to have one. A respirator is also recommended if you are spraying indoors as well as eye protection if you are shooting urethanes. ( should wear them for most paints but i know how stubborn we can be ) think of what you are inhaling if you do not spray in a well ventilated area, not only the carrier solvents but the pigments themselves which are designed to HARDEN to create a hard protective shell of paint. do you really want that in your lungs? nah… me either.

i have probably missed out a few things here and there, feel free to leave comments on this section and i will add anything i can to help anyone out.

in Part 3 i will go into the setup process and also laying down color coats.

cya then