The disappearing nine-patch is my new favorite block. It’s so simple to make, but looks like you pieced together a ton of small squares and rectangles. Great effect with minimal effort—my kind of thing.
Take these, for example. Just some basic nine-patches—all the same.
Then, they are cut into quarters.
And sewn back together into a four-patch.
To become all of these!
See? Simple-looks-complicated. Lovely.
If you don’t want to do the calculations, here’s a table of sizes:
|Starting Square||Finished Block|
|Common precut sizes are bolded|
Unfortunately, some common block sizes, like 6″, 8″, and 12″, end up requiring the starting squares be cut to third-inches, so I didn’t include them above. You could try rounding up to the nearest eighth, and use a generous ¼″ seam for the nine-patch piecing (and back to an exact seam for the four patch)—if you’re adventurous and aren’t concerned about absolutely perfect points.
Otherwise, the math isn’t that hard for these once you know how to do it.
To calculate final size from your starting squares
Example using 3″ squares.
Short answer: (Square Size × 3) − 2″
Example: 3″ times 3 equals 9″; 9″ minus 2″ equals 7″. 3″ squares make a 7″ disappearing nine-patch block.
- Add together a row of squares. Example: 3″ times 3 pieces (a row) equals 9″
- Subtract the row seams (½″ per seam, two seams). Example: 9″ minus 1″ equals 8″
- Subtract the four-patch disappearing seams (½″ per seam, one seam). Example: 8″ minus .5″ equals 7.5″
- Subtract your final piecing seams for the finished size. Example: 7.5″ minus .5″ equals 7″ finished block
To calculate starting squares from finished block size
Example needing 5.5″ finished block.
Short answer: (Finished Size + 2″) ÷ 3
Example: 5.5″ plus 2″ equals 7.5″; 7.5″ divided by 3 equals 2.5″. 2.5″ squares make a 5.5″ disappearing nine-patch block.
- Add your piecing seams to the finished size. Example: 5.5″ plus .5″ equals 6″ unfinished block
- Add your four-patch seams (½″ per seam, one seam). Example: 6″ plus .5″ equals 6.5″
- Add your nine-patch seams (½″ per seam, two seams). Example: 6.5″ plus 1″ equals 7.5″
- Divide by 3 to get your individual square size. Example: 7.5″ divided by 3 equals 2.5″ starting squares
Have fun with your own disappearing nine-patches! Let me know what you make, I’d love to see it.