I have a Badger Airbrush which is about 3 years old now. It's the one with the cup served underneath and it's double action. I have two types of needles and its respective nozzles. One is Fine and the other one medium. I use the medium for the nomral large area coating. The Fine for detailing.

But recently it the fine never sprays "fine' anymore. Now if you tell me to clean it I have "cleaned" it. It's cleaner than my room. The problem is whenevr I push on the "button" and slide it slowly to release the paint; it doesn't do that anymore. Instead it bursts out suddenly. Leaving me with a sploched camouflage.

Does anybody here had the same problem before?
Could you tell what's wrong with it?

Sounds like a damaged nozzle. You say the medium works fine, as it should? Then it's something wrong with fine nozzle/needle. You know, these things don't last forever. I say buy a new pair, it is cheap.

Been using badgers for about 30 years now. They make a tool, can't remember the part number though. It is designed to 1. to clean the tip on the inside, and 2. to remove the tip, and replace it, without damage to the rest of the head. (No need to replace complete head assembly).
A new tip will run you about 3 bucks, as to 14 for the entire head, and over the years I have learned to also replace the needle with the tip.
You simple insert the tool gently into the tip, from the inside, (It's like a triangle reamer) I first try cleaning the tip, dip the tool in thinner and gently rotate, and then flush the tip with thinners. and try using airbrush. it no luck, then replace tip. using the same tool, insert, apply gentle pressure, and it should unscrew the tip from the head. To install new tip, put a little bees wax on threads of tip, gently screw tip in place, insert tool, and with gentle pressure tighten tip.
Takes a little practice, but still using 30 year old head, just replaced tips over the years. (I always tell people I really am cheap). But once you get the hang of it, you'll find the heads last forever. Also replace the little teflon washer behind head at same time.
To check you needle, simple drag it under it's own weight over the back of your thumb nail, if it's bent (fine needles bend really... really easy) rotate it as you drag it, you will feel it snagging. you can either try straightening it, or replacing it.
As I said, I usually replace the tip and needle at the same time.
Hope this makes sense, it's really easier to do, than try to explain it.
I clean my tips a little different than most also......
I use one of those cute plastic eye droppers from Model Masters.....
got two, one cut down until I can screw the head onto it, and I insert it into a jar of thinners, and simply squeeze the thinnners in and out cleaning the head under pressure, and backflushing at the same time. The other I sanded a little until it fits snuggly into the bottom of the airbrush cup holder, I use this for fast color changes to force the thinners through the airbrush. I insert the airbrush into a jar of thinners, and simply again suck the thinners in and out, with the needle pulled back, and not depressing the airvalve.

I recently had a similar problem, because I dropped the airbrush while the finer part of the head was already unscrewed, dropping it right on the needle and needle head....
I managed to get the needle almost perfect again, but the small part on top of the head was bent.
I already bought a new needle, which wasn't cheap at all overhere (8 euro, about 10 dollar), and managed to fix the head myself a little bit .. (atleast it sprays again)
A new head costs about 25 euro overhere, that's about 30 dollar., which is a total rip off....
I searched for a list with replacement part numbers for badgers, but was unable to find them... Does anyone know if and where such a list could be found?

Just another small question... with a fine needle and needle tip, just how small would someone be able to spray a line?mine goes about 3 mm now, never been able to get it finer than that. Any tips or tricks to get it smaller?

Try the badger website. ..... http://www.badgerairbrush.com/