Below is the standard formula for reducing or enlarging.
- What is the original block size? e.g. 6 inches
- What size do you want the new block to be? e.g. 8 inches
- Divide the new size by the original size, e.g. 8 ÷ 6 = 1.33.
- Move the decimal point two steps to the right to get your percentage = 133%.
- Enter 133% into the copy machine to enlarge your 6-inch block to an 8-inch block.
- Do the opposite of above.
- Divide the small size (e.g. 6") by the large size (e.g. 8") to get your reduction percentage, e.g. 6 ÷ 8 = 0.75 = 75% reduction.
Proportional Scales may look a bit intimidating at first but they're easy to use. You can buy a Proportional Scale especially for quilters HERE.
How to use a proportional scale:
- On the bottom wheel, find the original size of your block (e.g. 6"), [Fig 1].
- Line up this number with the new size (e.g. 8") on the top wheel, [Fig 1].
- In the window, you'll see the percentage of the reduction or enlargement you need to resize your block, [Fig 2].
- Find the original measurement on the left side of the chart.
- Go along that row until you get to the measurement you want on the top row.
- The number in the intersecting box is the percentage you'll need to reduce or enlarge your block.