Around the House

#37 · Ruler / straight line guide

In a pinch, a standard chopstick is roughly 23 cm long - useful for rough measurements when your actual ruler has vanished.

A standard chopstick is around 23cm long and dead straight - shorter than a 30cm ruler, but longer than most things you need a straight edge for. It won't measure anything, but for ruling a clean line when the ruler has vanished it's perfectly good.

How to do it

1. Lay the chopstick along the intended line and hold it with fingers spread wide rather than bunched together.
2. Run the pencil along the edge in one stroke, keeping the pencil upright.
3. Lift straight up rather than sliding, so you don't smudge the line.

Why it works

Bamboo grows in long parallel fibres and splits along them, so a chopstick is straight along its length as a consequence of how it was made rather than how it was finished. That is also why it stays straight - there is no stress locked into it waiting to warp.

Tips & warnings

• Chopsticks with a flat or squared face give a much better edge than fully round ones - Korean-style flat metal ones are best of all.
• Mark one in centimetres with a permanent marker once and it becomes a genuine measuring tool that lives in the drawer.
• It will rock if the face against the paper is curved. Find the flattest face first.
• For anything over about 20cm, use a real straight edge - two lined-up strokes never quite meet.