Fine line tutorial
Picture of By Barbara

By Barbara

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Painting fine detail with a brush

Fine detail can be tricky and we tend to prefer using a pen for detail because we’re used to pens. The problem with paint pens and gel pens are that they are not well suited to rock painting. The rock surface is different to paper, rougher and more abrasive, and the pens tend to clog, bleed and stop working way before their time, leaving you with an expensive paint pen that no longer works.

For fine linework, you’ll need a very fine brush. The best I have found is a 4/0 brush (also marked as a 0000 brush). For this exercise, you’ll also need Lily White paint, a palette knife if you have one, a pencil or a white pencil, a piece of scrap paper or board (not white) and a ruler. We’re going to get the feel for the brush and paint on scrap paper first and it’s best to use brown paper or something similar because the white paint won’t show up well on normal white paper.


To start with, we’ll draw some guidelines onto the brown paper / card. The best way to use a brush when doing fine work is to work from left to right (if you’re right handed) and to work at an approximately 30º to 45º angle from your own body. I have managed to find and dust off a set square for this exercise but you can just draw the lines by approximation. As you’re working with the brush, you can adjust the angle for yourself by swiveling the card, as you discover what’s most comfortable for you.

Using Lily White paint, give the closed bottle a shake, open the lid and remove a blob of paint using a palette knife. If you don’t have a palette knife, just use a strip of card. Place the blob of paint on a mixing dish. This could be a plate, a yoghurt lid or a specially made paint mixing dish.


Dip your brush lightly into water and swirl a bit of white paint from the edge so that some paint sticks to the brush bristles – only about half way up the bristles, no more. The paint on the brush should not be so thick it makes a ball of paint, so the tiny bit of water on the brush will help get the right consistency which should be like thick cream.

Hold your brush with paint in position, ready to start applying the paint to the lines on your card. Now, here’s probably the main trick. You’re not going to use the brush as if it were a pen or pencil, you’re going to drag it very gently and steadily as if it were a little bird’s feather, keeping the pressure constant. This may take a few attempts to get used to which is why practicing on card beforehand and also while you are working is very helpful. To steady your hand, you can rest it on the work area surface as you would for a pencil. If you suspend your hand above the work area, your lines could turn out a bit wobbly.

The paint line will be an even thickness as you get started but as the paint leaves the brush and goes onto the card, the line will start to taper off. Dip your brush into the paint again and carry on with the line just before you left off, continuing until it starts to taper off again. Then start a new line, and another, and another, carrying on until you feel you’re getting the hang of it.


After working for a few minutes and doing a few lines, the paint might start to dry on your brush. The warmer the air temperature around you, the quicker the paint will dry. To prevent the brush clogging up with half dried paint, give it a wash or rinse regularly. The 4/0 brush is very delicate and needs to be carefully looked after. When washing, dip it into water but not all the way to the bottom of the water jar, only swivel it lightly on the inside of the water jar, just under the water level, so that the paint loosens and the paint dissipates. Swirl it a bit more against the side of the water jar to make sure it’s completely clean. Then dry the brush on a piece of old dishcloth by holding it almost horizontal, allowing the water to seep into the cloth. With your fingers, give the bristles a little gentle squeeze to re-shape. Then you can continue.


Let’s paint a simple leaf
Choose a nice smooth rock, smooth rocks are better for fine detailed work. Using a white pencil if you have one (a normal pencil if you don’t), draw a gentle arc through the middle of the rock – this is the stem and leaf centre.
Then mark out the leaf area and then the veins. Pencil is easily erased so if you’re not happy with your marks, erase and start again. Once the leaf is drawn, mark out a border around the edge of the pebble.

As you did in your exercise, dip your clean, wet brush into your paint which is on a paint dish. Make sure the consistency is right and start painting your line. If you are not happy with it, you can wash it off with a damp cloth and practice some more before trying again. Once the centre line is painted and the paint is dry (it will dry quickly), paint the leaf shape. Once this is dry, paint the veins, taking care to paint short lines that do not quite reach the edge of the inside of the leaf shape.

When your line work is complete and dry, take a larger brush, I recommend a Round 1 brush, dip into the paint and begin to fill in the area around the outside of the leaf, up to the border marked around the edge of the pebble. Continue painting the first layer of flat white all around the leaf, keeping a good straight edge around the side of the pebble. You should hold your brush at the same 30º to 45º angle that feels comfortable while painting. Once you have painted all around the leaf, allow the paint to dry properly and use an eraser to remove any visible pencil lines. Then give the white area a second coat of white paint.

When the outside area is dry, use a dotting tool or a toothpick or the front of a pencil nib, dip it into your paint and carefully dot the ends of the vein lines. Do this to all the vein line ends, being careful to leave a small gap between the inside edge of the leaf, and the dot. Allow the dots to dry before varnishing your pebble with a clean, broader flat brush. The varnish will also bring out the lovely natural colour of your pebble.

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