How to sew a corner seam

Sometimes you want to insert a square corner into a piece of fabric. You may find this type of colorblocking on garments, but it could have many other applications. How do you do it? It’s a simple technique. Let’s give it a try!I’m interested in knowing any other names for this type of technique. It seems I used to know it as something else, but forgot what it was called. If you have a name for it, please comment below! (UPDATED: One reader suggested “inward corner” or “inset corner.”)


(Click fabrics for direct links for purchase at Warehouse Fabrics Inc.)

The process

Spiral French Blue/Kelso

Dottie Kelso Brown/French Blue

This isn’t a garment or anything, so I’m just doing an example starting with a rectangle of fabric. Say you want to replace that little square that I cut out of the bottom with another piece of fabric.In my example, I cut a 5″x5″ square out.
I want to replace it with this fabric. For my example, to replace a 5″x5″ square using 1/2″ seam allowances, I had to replace the square with one that is 6″x6″.
For the purpose of example, I have drawn my 1/2″ seam allowances. But I recommend you do it, too, because it is imperative that you stop right at the intersection of the lines.
Place your fabrics right-sides together on the top seam line, as shown.
Sew from the end to the spot where the lines intersect.
You need to clip the bottom (main) fabric diagonally up to that point, but most definitely not through it!It may be easier for you to do this if you remove your fabric from the machine, though I did another one and managed to do it while leaving it in place, with the needle down to keep things from shifting.
If you removed your fabric, replace it now and put the needle in the down position right where you stopped sewing.
While holding the top piece of fabric, pivot the bottom piece so that the other edges of the squares are now aligned, and sew down that side. After pivoting, but before you start sewing, really make sure that the bulk of the fabric is out of the way of the needle so that you get a smooth corner. That means feeling underneath the top layer around the pivot point to make sure that the fabric is pulled to the side and up.
Press your seams open and steam the corner from the right side to get it as smooth as possible. Don’t rub the iron back and forth — you may stretch or distort the fabric. Just lightly press and steam, steam, steam!

Other views

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