|All the knots on this website were, of course, made on my computer. So perhaps it is time to add something about making computer Celtic knots.
The main difference is obviously that you can rub out cleanly. You can also fill in colours quickly. Once you can made one piece of a repetitive pattern, you can copy and paste it to generate a larger design very easily. Also, if you design at the pixel level, you can make the knot completely accurate.
When I design a pattern, I start with the basic width of the strand or ribbon. The easiest is a strand of some colour, with a thin edge of some other colour on either side. This shows the under-and-over well. You must then decide how close the strands lie. It is possible to have the strands so close together that there is only one dot between them. I prefer the gap between the lines to be as wide as the strands themselves, as this leaves room for smooth turns.
You can also have strands without edges. These will need a gap between them, as otherwise the under-and-over gets confused. These simple strands can be threaded in pairs. This makes the eye 'see' a strand between them. This is common in the Book of Kells knots.
You can also have a more complex strand, with edges of a different colour, separated from the main strand with a black line. This needs some careful thought about the gaps, or you will not be able to turn the strands smoothly. I've had to do some designs more than once until I got the gaps right.
Now, you must decide how wide to make the strands. I have made the knots as small as possible, partly to save room on my computer, partly to make them quick to load, partly so you can see complex knots on the screen all at once, and partly because my mouse hand is aching quite enough as it is! This means that I have made the thin lines, such as the edges, one pixel wide. Then build up the other dimensions from that. This means that you don't make a knot to fit a gap - make the knot first, and build up the rest of the design around it.
When constructing knots, I advise zooming in until you can see the individual pixels. The secret of a good Celtic knot is regularity. If you are drawing lines by eye, then you can 'drift' spatially, and then the knot won't join up.
To get you started, I've made some big grids for you. Use the turns round the edge with copy and paste to start making your own knots. The first grid is the strand with a single edge. The second is the simple strand. The third is the strand with the complex edge. For the third, I've given a background of dark red rather than black, since black is used to separate the edge from the middle of the strand. The fourth grid is a strand with a simple edge, but close-weaved, with tiny gaps.
If you are constructing a bulky knot rather than a border, try constructing half, or even a quarter of it. The copy it and rotate the image through 180 degrees (or 90 degrees). Then paste it back. You will find that 'mirror' or 'flip' won't work, as the under-and-overs get muddled up. But rotating through a right angle should.
|Here is an example of a Celtic knot. I made it using the first grid above. I constructed this knot around the idea of an octagon divided into sections. You can leave the knot all in one colour, or you can colour it in various ways, which high-light different parts of the knot. Making the background dark or light gives different effects as well.|
|You can use different grids for different effects. The close-weave grid has practically no gap, so you must allow room for a curve. This means you can see the individual knots easier. The looser weave allows the knots to be packed closer together, so they blend into one pattern.
You could pack the close-weave knots closer together, but then the individual knots would be on a different grid. This wouldn't matter if it was a simpler border, but if you were making a more elaborate pattern, then drifting off one grid onto another might mean the pattern wouldn't join up somewhere else.
|Felt-tip pen method|
|Copying Celtic knots|