Draw fine lines
It may seem easy. To draw a fine line with a brush. But making a really nice line with a brush can be tricky. Many of my students have problems with this.
Use a “dry” brush.
If you want your brush to give a narrow line, it is very important that it is not full of color. A wet brush causes the straws to swell and the top becomes thick. When you need a really nice result, the brush just needs a little color in the hair. You accomplish this by pulling off as much paint as possible on the edge of your mixing cup. It does not matter if you use dark or light color. When you think you have emptied the brush of paint against the edge of the mixing cup, it is only half empty. Repeat this, and again until no paint comes off the brush.
When your brush is drained of paint, you can get very fine lines, of course the quality of your brush also matters, it is much easier with a good brush.
Hold the brush correctly
If you hold your brush at 90 degrees to the paper, it is possible to create a fine line, if you, on the other hand, tilt the brush and hold it like a pencil, you get a larger contact surface against the paper and a wider line. It is not easy to hold a brush so upright, it feels unnatural, but it is necessary if you are going to make a narrow line.
Have support for the brush
The slightest variation of the pressure of your brush on the paper will result in a narrower and thicker line, respectively. It is therefore important that you can get the same pressure if you want to obtain an evenly thick line. I usually use my middle finger as support. My students think it feels strange, In that case try with support from the whole hand, That you have some kind of support is important. If you only paint “freehand”, it is impossible to get even lines.
Do not use your wrist and fingers when painting
Most people are unfamiliar with the brush but accustomed to writing with a pen. When writing with a pen you use your fingers and wrist to control the movements of the pen. When you paint, this familiar way no longer works. When using a brush for painting, use the whole arm, with “locked” fingers and wrist. When using the wrist, all lines become slightly curved (to the right for right-handers and to the left for left-handers). To compensate for this, it is common to paint many small lines in a row to create a coherent line. Instead, try to draw a long line, it will be much better.