Grid enlargement calculator
Enter the grid a small pattern is drawn on and the width you want it enlarged to. This works out the size to draw each square on the full-size grid, so the pattern copies over line by line.
in
in
Draw the full-size grid at
4"per square
Scale factor
4×
Full-size height
16"
About enlarging a pattern by grid
- How do you enlarge a pattern using a grid?
- Draw the small pattern on a grid of equal squares, draw the same number of squares at full size, and copy the lines over one square at a time — where a curve crosses the third small square a third of the way down, it crosses the third big square the same fraction of the way down. The only arithmetic is the ratio between a small square and a big one.
- Why not just use a photocopier or a projector?
- Either works for a pattern that fits the equipment. The grid method scales up to any size — a full corbel, an arched apron, a cabriole leg template — using nothing but a straightedge and a pencil, which is why it's the traditional way patterns this size have always been enlarged in a shop.
- Does the grid have to be square?
- Yes — a rectangular grid stretches the pattern unevenly, distorting curves in one direction more than the other. Keep every square on both the small and the large grid equal on both sides, and only the overall size changes.