I am a Painter and Decorator by trade, I also did much sign writing years ago before tradition went out of the window with the advent of plastic and vinyl signs, My work also involved a lot of pin-striping, I personally did not use the special short handled long haired brush you've seen used for the this fine art, the reason was that most my work revolved around lettering on company vehicles and shop signs, mostly on the shop signs was there pin-striping involved. The difference between the 2 types of brushes is, the sign-writing brush has a long handle with sable hair between 2 and 3cm long varying thickness's for different size letters, they can have a pointed tip have a chisel edge, pointed tips are great for making sharp corners although this was possible with the chisel edge which I always used, the chisel edge was ideal when there was pin-striping involved because it was easier to achieve a uniformed thickness of line. The pin-striping brush has a very short handle and has hair between 6 to 8 cm or longer depending on the thickness, the hair is also very wide at the ferrule and decreases in width as it nears to the point, some of them are also slightly chisel edged, but the main reason for difference in form is that the pin-striping brush is designed hold a vast amount of paint which allows the user create extremely long continuous and uniformed lines, thickness of line can be controlled by increasing or decreasing pressure on the brush, the short handle is held in the palm of the hand and the index finger is placed over the front of the ferrule ans close to hair as possible, this is as if you were pointing at the work, the pinky and next finger are used to guide the brush and also keep it steady. The biggest problem with a tutorial and I assume the reason no one will do one, is that there are certain aspects of the art which cannot be taught, the main one being the steady hand required, but also your brush will behave differently using different paint, automotive and oil-based paints behave and work better than water-based due to the finer pigments. The good news for those of you wanting to learn how to do this is that if you have been airbrushing for a while and can control your airbrush good enough, and understand the importance of distance from the work surface, you already have 2 of the most important skills required to carry it out, the rest is the same as airbrushing, simply practise until you get the feel of it, you will be surprised how easy it actually is. I would be more than happy to make a video of the process and and describe what is happening, however I feel this would be pointless because it would be pretty much the same as any other video you've seen, it not easy to describe anything while working because there is high degree of concentration required (one other trick no one can teach you) this would mean stopping in the middle of a line and with pin-striping that just isn't wanted because it would create a seam in an otherwise perfect line. The best advice I can give you is to go buy a pin-striping brush of medium size, it doesn't matter if it's cheap as long as it has real hair and is not synthetic, e.g. nylon or polyester, have a little play around and discover that you have more talent than you think, you can use your normal airbrushing paint for practising or literally any kind of paint, bearing in mind thickness will influence the behaviour of the brush. One last important factor, when airbrushing the closer you get, the thinner the line, with pin-striping this is reversed, the closer you get (more pressure on the brush) the thicker your line. Since I've taken the time to post this I would love to see some of your progress, so go to it guys, shock yourselves, and just Maybe our friend and mentor Mitch will put something up for best beginners piece. P.S. should you decide to have a go and you get stuck, do ask, I'll keep tabs here and answer all your questions, good luck.