I've used Botch... er...Badgers for years, as well as my trusty 'ole Pasche H model. I was able to net good results from all of these, but I used different brushes for different purposes. The Pasche was a good one for laying in the base coats and for one-color shemes. The Badgers were good for detail work, and I preferred the single action. (Single action brushes have separate controls for paint flow and spray pattern. Double action brushes incorporate both functions into the trigger action.) I wanted to use the double-action Badger I had, but it was rather awkward. Didn't feel right.
Finally, I got-a-Iwata!
An Iwata Eclipse, to be exact. This is the first double-action brush that has felt comfortable to use. I'm in complete control (unlike the old Botcher) and it performs like a dream. It's easy to maintain and doesn't have a maddening teflon bearing buried inside the body. Iwatas are fairly priced, as well. I got mine at a local Art store. Their price was $99. The whole enchilada (brush, compressor with trap & guage and air line) was around $230. The retail will be more, especially seeing as you're from the Great White North, but it's well worth the investment. Having said all that, which is my opinion and my preference only...
Here's what you may want to do. Do you know anyone who has an airbrush? Ask them if you can take it for a test ride. That's a good way of seeing if a certain brush is for you. I tried all sortsa brushes before I settled on the Iwata. It's also a good excuse just to hang with your modeling buds. Good 'ole Mike (aka Butz) and I have spent many a night in his or my basement tinkering with a kit, painting etc., as well as just shootin' the breeze.
You may wish to look at not only the action type (double or single) but the paint feed type as well.
I've found thru experience and snooping around that sometimes it's not the type of brush that is important. It's the skill of the user. Skill is something that, for most, has to be developed. So the word there is PRACTICE! I got great results with a single action. Some swear that it's impossible to get good results with a single action brush, but I have a few built-ups as proof to the contrary. As far as paint feed, I will never go back to a siphon feed brush. Gravity feed is the way to go, hands down. It's just simple physics at work there. (A siphon feed brush has a cup or bottle that you "plug" into the bottom or side of the body, using the vacuum created by the air traveling thru the brush to suck the paint up or over into the airstream. Gravity feed brushes usually have a cup built into the top of the body and the paint simply flows into the airstream.)
Air supply is an important factor. Compressors are the way to go, if you can afford one. But they're not all that expensive anymore (depending on the type you get, of course!) and they're also much quieter than they used to be. (again, depending on type) You can spray off of a potted air source, like a tank or propellent cans. The propellent is not all that great, and tanks are okay until they empty out, then there's a gradual decrease in air pressure which is uncontrollable and not good when you're in the middle of painting some finely detailed stuff. My advice: go with the compressor.
Remember, there are many variables involved, many of which are determined by one factor. The human factor, ie you! Test different brushes if possible, find one you like, and practice ALOT.
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