Measuring and marking out accurately
Design & Technology · Key Stage 2 · The School
Marking out first
MARKING OUT means drawing the exact lines you will cut, before any cutting starts. Skipping it and cutting by eye feels quicker, but it is where most wasted material comes from. A few careful minutes marking out usually saves far more time later. Rushing this step is one of the most common reasons a project goes wrong.
Using a ruler and a right angle
Line the ruler up with both ends of the measurement, not just one. Make a small, clear mark. Do not draw a long, scribbled line. A set square checks that a corner is a true right angle. A corner that looks straight to the eye is very often not quite ninety degrees.
Small errors add up
A part that is two millimetres out does not look wrong on its own. Join four such parts together. The errors add up, and nothing lines up any more. This is why marking out is checked before cutting, not after. A mistake found early costs a pencil mark. A mistake found late costs the material. It is always worth checking twice before the first cut is made.
A box needs four sides and a base marked out on one sheet. Measure and mark the base first: a rectangle, checked square with a set square. Then mark each side, measuring from the base's own edge each time rather than guessing. Checking every measurement against the base, rather than against the last piece marked, stops a small early error being copied into every piece that follows.