airbrush question

im going out to buy my first airbrush 2moro.im only getting a cheap on as i cant afford a really good one but i was just wondering,if anyone has had good results from using an airbrush with one of those cans with compressed air in it instead of using a compressor?

You can get a reasonable finish from the compressed air cans, you just have to vigilant of a few things.
The actual gas in the cans is CO2, then this is discharged from the can it cools rapidly, after a few moments of spraying you will notice a significant temperature drop in the feel of the can as well as the air coming out the airbrush. If you spray long enough, the air line can freeze, you will also see a decrease in viscosity of the paint you're spraying as it gets cooler.
You can counter the cooling effect by standing the can in a pail of warm water while you're spraying - warming the can will help minimise the temperature loss. Please note I say warm - you want water you would be happy to bathe a baby in, too much heat to the can will be a bad thing!

Secondly, when you use these cans, you have little to no control over the air pressure from them (it will decrease as the cans cool too!), if you're going to optimise the use of your airbrush, you really want a controllable air supply. The cans are fine for starting out, but if you wish to progress and develop better technique, you won't want to use them for too long.

I agree, performance of cans is poor, and they're not cheap, and they don't last long! You're really p*ssing money away with cans, before you know it you'll have spent as much as a basic compressor. If you really need to save money I guess you should not use those cans, maybe an inflated tire tube or something, but the sheer pleasure of using a compressor is worth it - if you can possibly afford one, you really should look into it. Try ebay perhaps?

thanks mate,do you know how much the cheapest airbrush and compressor set is that i could get instead of going the compressed air can route?

It depends on your budget really - you can get anything from a Testors starter set to something like Hiroboy sells:
http://www.hiroboy.com/catalog/product_info.php?products_id=498

How much are you looking to spend?

My honest opinion is that cheap airbrushes and compressed air cans are a false economy in the long run; airbrushes are merely a vehicle to get the paint on the model, it's no harder to learn on a good brush vs. a cheap brush, you spend your time learning how to adjust your paint/thinner ratios and air pressure, and most of the quality of your paint is also determined by how good you do prep work and sanding/polishing. I'd rather someone get good at using good spray cans like Tamiya or Testors lacquers, and whilst doing so save up for a quality airbrush and compressor-especially a compressor, as those cans of air are very expensive. I started airbrushing w/a dual-action Badger and bought a compressor for it, and never looked back. While you can get decent results w/a cheap airbrush, you can find good deals on excellent airbrushes and compressors if you look around. I bought a cheap (under $15) Wal Mart airbrush and compressed air to use as an example vs. other airbrushes, and found the performance pretty miserable.

Do what half the world does and get a single-action Paasche Series H on eBay or from a dealer. Be sure to get the three standard nozzles, #1, #3 and #5 - I think the #1 is the most useful, but YMMV. To paint car models, you don't need to paint 2 mm wide lines, and you don't need a double-action brush.

Paasche Series H's are inexpensive, but they are not cheesy or cheaply made. They are sturdy, mostly metal, and will do a perfectly good job on model car bodies. They are a delight compared to rattle cans, which spew out way too much paint for either good air quality or good control. When I spray with a can, I always spray outdoors.

Get the kind of compressor that doesn't require a tank. Badgers are reasonably quiet and will run forever without attention.

Be sure to get a regulator/water filter/gauge, and set the gauge for 25 psi for starters. Use hoses that are plenty long - 12 to 16 feet. (The hose length gives you more flexibility and absorbs pulsations from the compressor.)

Handy accessories include a foot pedal on-off switch and an airbrush holder. You'll need someplace to put your brush when you're not spraying.

Get a color cup and some extra Paasche siphon-fitted jars. Small ones are the most useful, IMO. Get a can of hardware store lacquer thinner for cleanup and to thin your paint way more than seems reasonable - at first.

Always wear a professional painters' respirator during and immediately after spraying. Your health is worth more than $40, isn't it? (I happen to be allergic to lacquer thinner. If I spray without a mask, I get a cough, insomnia, stomach pains and light-headedness for 3-4 days. No fun, believe me. But if I wear the mask, I feel just fine - no symptoms at all. Tells you something, doesn't it?)

Shoot plenty of straight lacquer thinner through the brush before and after every session. Take the nozzle apart and clean it well - with lacquer thinner - after every fourth session. Avoid getting the lacquer thinner on your hands, and if you do, wash up right away. (It penetrates the skin.)

Always test the brush before aiming it at a model. If it doesn't spray freely, or rains big gooey drops, you probably haven't thinned the paint enough. Never try to rescue a paint session that's gone bad by adding more paint. Just... STOP. And then, as you clean the brush, etc., calmly plan your next move. (Hint: Despite its toxicity issues, lacquer is the most forgiving type of paint.)

Use thinner to control the thickness of the paint. Use the nozzle adjustment to control the amount of paint/air mixture. Use speed and distance from the model to control the wetness of the coat. Initial coats should be light and dry (brush more distant); the final coats should be wet and thin (brush close and sweeping rapidly).

Did I say to thin your paint a LOT? Well, I should have.

Have fun!


Diddy

is this anygood or not?

http://cgi.ebay.co.uk/COMPLETE-AIRBRUSH-KIT-AIR-BRUSH-COMPRESSOR_W0QQitemZ140195163920QQihZ004QQcategory Z16705QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Be sure to get a regulator/water filter/gauge, and set the gauge for 25 psi for starters. Use hoses that are plenty long - 12 to 16 feet. (The hose length gives you more flexibility and absorbs pulsations from the compressor.)


I've got a regulator/water filter/gauge set up, but I could never understand why shoot it at 25psi?

I tried 40 psi and it wrinkled my painted, like it blew it too hard while it was wet!

What is the best psi to shoot? 25 seems to come out almost dry

What is the best psi to shoot? 25 seems to come out almost dry

There's no "best" psi, but 25 is a good place to start. You don't need more pressure than is necessary to produce a good aerosol spray. Once you've got enough for that, use other means to control things like volume, wetness/dryness and paint thickness.

As I said in my post, "Use speed and distance from the model to control the wetness of the coat." If the paint is too dry when it lands, try holding the airbrush closer to the model.

Diddy

The psi you shoot at is dependant on the paint type and how thin it is when spraying. I shoot most lacquers in the 15 - 20 psi range depending on how thin the paint is.

You can achieve different textures with an airbrush by adjusting paint thickness and the air pressure, you just have to understand how to do so.

Sixx, the 'wrinkling' you witnessed was a result of too much paint being laid down at too high a pressure. Try to spray in thin even coats at the lowest possible pressure you can spray effectively at.

is this anygood or not?
I like the kit idea, and it looks like a lot of stuff for the money, even taking shipping cost into account. But the manufacturer is not identified. And, most important, it looks like more confusing complexity than you need at this stage. I'd still go with a single-action, medium-tipped, name-brand metal brush like Badger, Iwata or Paasche.

You don't need anything more elaborate to paint model cars, and probably never will.

Diddy

Be sure to get a regulator/water filter/gauge, and set the gauge for 25 psi for starters. Use hoses that are plenty long - 12 to 16 feet. (The hose length gives you more flexibility and absorbs pulsations from the compressor.)

Diddy


Diddy,
when you say shoot at 25 psi for starters, do you mean for beginners?
When I shoot at 25 psi, it seems like the paint comes out almost dry and I gotta get right up on the model. Though, when I shot it at 40 psi once, the air was so strong that it blew the paint while it was wet and wrinkled it. That was a major pain in the ass to sand out!:grinyes:

Diddy,
when you say shoot at 25 psi for starters, do you mean for beginners?
When I shoot at 25 psi, it seems like the paint comes out almost dry and I gotta get right up on the model. Though, when I shot it at 40 psi once, the air was so strong that it blew the paint while it was wet and wrinkled it. That was a major pain in the ass to sand out!:grinyes:
I'll bet.

Whether 25 psi is too much or too little depends on the nozzle diameter and other factors like air pressure and ambient temperature. But a good rule of thumb is to use just enough pressure to create an aerosol (spray), and no more. But I actually don't think air pressure has anything to do with the dryness you talk about.

Basically, the solution to dryness is to move closer to the model, so the paint doesn't have a chance to dry on the way to the model. But if you're right up on the model and it's still dry and gritty, you're either just dusting the model by moving too fast, or you're not thinning your paint enough. The chances are it's the latter.

When I constantly read about people using abrasive "finishing systems" and sanding their final coat of paint, I have to think that most modelers don't add enough thinner. If a sprayed coat of lacquer has so much orange peel that it needs to be sanded, it was either too thick to begin with or the airbrush was held so far away that the paint dried and thickened on the way to the model.

From your description, it sounds like that same ol' thick paint problem. For starters, run a test by adding about 30% more lacquer thinner to your paint. Try spraying an old car body from a normal distance, and let us know how it turns out. Good luck!

Diddy

Freakray and Didymus are both offering great advice. But I think the take-away from both of their recommendations is that there are too many variables making hard and fast rules about airbrushing techniques. I'm like Freakray and spray about 25 psi, but have had occasion to go higher depending on the brand of paint, brand of airbrush, nozzle, and time of day, I spray. I've never had occasion to go to 40 psi, though.

The general consensus here seems to be that you should save your money and invest in a good quality airbrush and compressor. The Paasche mentioned by Didymus is a very good airbrush for car modeling.

The compressor can be a good choice but be sure that the pressure that they put out is greater than what you think you'll need if you buy a regulator. The regulator can only lower the pressure. So if your compressor works at 25 psi then the regulator can only start at 25 psi and go lower. Since 25 psi seems to be too low for many modelers it may not be a good choice as you will have little or no practical control on the pressure. For example the Testors AC200 might not be a good choice at 25 psi but the Testors Blue Ice would be a better choice at 40 psi because, with a regulator, you can turn it down to 25 psi and cover the pressure range you'll probably be working at. I'm not suggesting that you buy either as I don't use them and can't say how good they are. I used them only to illustrate my point.

All this being said be sure to price the standard home-garage air compressors. You know, these are the ones that you can wheel around and use your air tools on. They can be priced comparably to the hobby-style compressors and have the added features you will need. These are indeed more practical as they can be used for home DIY projects. However, if you are going to do your airbrushing indoors the home-garage air compressors may be a bit too unwieldy around the furniture.