The illustration shows a four-patch block next to a nine-patch block. Notice that the patches don't match up very well because of the differing grids, giving the combo an uneven appearance along intersections.
If that isn't the look you want, choose blocks with similar grids or use sashing between blocks to camouflage their differences.
Quilt Block Size
Analyzing quilt block construction helps you choose a block size. To rotary cut the fabric, choose a size with units you can accurately measure and cut with rotary rulers.Example:
To make a five-patch block that finishes at 10", divide ten, the size, by five, the number of grids across and down. The result, 2", is the finished size of each grid in the block.
Do the same for a 12" five-patch block. Twelve divided by five produces units that are 2.4", fine if you want to draft templates but not a size you can accurately rotary cut.
Choose Grid Size First
Approach block size from a different perspective by choosing a finished grid size first.
- Multiply a grid size by the number of grids across and down. For instance:
- A (subdivided) four patch block with 3" grids would be 4 x 3", or 12" square
- A five patch block with 3" grids would be 5 x 3", or 15" square
To mix blocks with different numbers of grids, find a size that works for both. Four-patch and nine-patch blocks can both be cut to finish at 12" square because their grids are easy to rotary cut when divided into that number: 12/3 = 4" for the nine-patch blocks; 12/4 = 3" for the four patch blocks.
- A (subdivided) four patch block with 3" grids would be 4 x 3", or 12" square
- Block units needn't be in whole numbers. Fractions are fine as long as they work with your rotary rulers.
