Two-colour printing: colour planning and alignment

1One more colour, much more impact

A one-colour print is bold; a two-colour print can show light and shadow, a shape and its outline, or a motif and its background. Many school badges, bank logos and football shirts use exactly two colours because they are clear from far away and cheaper to print. The challenge is alignment: making the second colour land exactly where it belongs on the first. Printers call this registration. With planning and a simple card guide, you can print two colours neatly by hand.

2Colour planning

1. Make a colour sketch at full size with coloured pencils, showing which parts are colour 1, which are colour 2, and which stay paper colour. The paper is effectively a third colour.
2. Choose two colours with different values: one light (such as yellow or a pale tint) and one dark (such as dark brown, navy or black). Two colours of the same value, such as red and green, blur together when seen from a distance.
3. Print light first, dark last. A dark colour covers a light one cleanly; a light colour printed over dark almost disappears.
4. Plan any overlaps. Where the dark prints over the light, you see the dark. With thin, see-through ink, the overlap can make a third colour, for example blue over yellow looking green.

3Three ways to print two colours with stamps

• Two blocks (colour block and key block). The colour block prints the broad areas in the light colour. The key block prints the outlines and details in the dark colour on top. Both blocks must be cut to exactly the same outside size, with the design in the same position on each.
• Reduction (one block). Carve the areas that stay paper colour, then print every copy in the light colour. Clean the block, carve away everything that should stay light, and print the dark colour on top of the same copies. You cannot go back afterwards, so print a few extra copies in the first colour.
• Two colours on one stamp. Dab colour 1 onto one part of the stamp and colour 2 onto another with two small brushes, then print once. Quick, but the colours can blur where they meet.

4Alignment (registration)

• Arrow on the back: draw an arrow on the back of every block showing which way is up, so it is never printed upside down or turned.
• Registration corner: tape an L-shaped strip of card to the table. Push the corner of every sheet into the L, so each sheet sits in exactly the same place.
• Pencil ticks: make two small ticks on the paper where two edges of the block must go, and line the block up with them for both colours.
• A see-through mount: glue a foam or rubber stamp onto a piece of clear plastic from packaging, so you can see exactly where it will land.
• A light grid for repeats: rule faint pencil lines one repeat unit apart (the stamp's width plus the gap you want), and start each print at a grid corner.

Worked example: ten two-colour cards

Keza is printing ten cards with a flower motif, using a yellow colour block and a brown key block, both 6 cm square.

1. Plan: she makes a colour sketch: yellow petals, brown outlines and centre, white card background.
2. Extras: some prints always go wrong, so she prints 12 cards, not 10.
3. Set-up: she tapes an L-shaped card corner to the table and marks two ticks 2 cm from the top and left edges of each card.
4. Colour 1: she prints the yellow block on all 12 cards, lines up with the ticks and the arrow pointing up, then washes the block and leaves the cards to dry for 30 minutes.
5. Colour 2: she prints the brown key block on all 12, using the same corner and the same ticks.
6. Count and choose: 12 cards × 2 colours = 24 impressions. On two cards the brown landed 2 mm too low, so she keeps the best 10.

5Make it: a two-colour edition

1. Make a colour sketch of your motif in two colours plus the paper.
2. Choose a method: two blocks, reduction, or two colours on one stamp.
3. Set up a registration corner and print at least six copies of colour 1. Let them dry.
4. Print colour 2 on all of them and choose your best five matching prints. Printmakers call a set of matching prints an edition. Number each one in pencil at the bottom (for example, "3 of 5") and sign it.

6Look closely

The German artist Albrecht Dürer (1471–1528) designed his famous woodcut of a rhinoceros in 1515 from a written description and a sketch, without ever seeing the animal. More than a hundred years later, after 1620, a publisher in Amsterdam printed Dürer's old block again, this time together with a second block.

• The black lines come from Dürer's original key block.
• The flat olive-green comes from the added tone block. Look for the pale shapes on the shoulder and the body armour: they were cut out of the tone block, so the paper shows through as highlights.
• From two blocks the printer got three values: pale paper, middle olive and dark black. That is colour planning with value, exactly what you did in Unit 2.

Practice