How to Sew Perfect Boxed Corners on Pouches and Bags
Boxed corners aren’t difficult. Most of the time, what you really need is a little help with accuracy. In this tutorial I’ll walk you through how I get perfect boxed corners every time using the cut-out square method and an acrylic template.
Here is my longer boxed corner demonstration for Beginners, this video is 14 minutes.
Here is a short 2 min Video Demonstration of making boxed corners on my channel, thank you for subscribing!
What You’ll Need
- An acrylic template OR measure accurately
- Your pouch or bag pieces
- Rotary cutter and/or scissors
- Clips or pins
- Quality thread (I use Gütermann)
- A blunt tool for pushing out corners (optional)
Step 1: Align Your Template on the Edges
Place your acrylic template at the bottom corner of your pouch so it sits right on the absolute edges of the bottom and the side. Lining it up with the raw edges, rather than measuring from a seam line, keeps seam allowance issues from throwing off your boxed corners.
Step 2: Cut Both Layers at Once
Cut the square out through both layers at the same time, making sure everything stays aligned. Repeat on the other bottom corner.
This is why, in my Easy Zipper Cases pattern, we sew the sides first. That way the two layers are absolutely together when you cut, and both corners match perfectly.
Step 3: Sew the Sides and Bottom with a Lock Stitch
Sew down one side of the pouch, along the bottom, and up the other side. Lock stitch at the corners. This helps keep them from pulling apart when you form the boxed corners.
Step 4: Match and Nest the Seams
Come in from the top of the cut-out corner and match the side seam to the bottom seam. Nest your seam allowances, meaning one goes one way and the other goes the opposite way. Nested seams lock together, which keeps your corner lined up while you sew. Flatten the corner and hold it with clips, pins, or whatever works best for you.
Step 5: Sew Across the Corner
Sew straight across the opening, lock stitching at the start and stop.
Working with vinyl or cork? Take a second pass just outside the first line of stitching. This makes the boxed corner very strong. For cork, I use a 3 mm stitch length.
Repeat on the second corner: match the side seam to the bottom seam, nest the seam allowances, lock stitch at the start and stop, and add a second pass if your material needs the extra strength.
Step 6: Trim, Turn, and Push Out
Before turning, trim the seam allowance down just a little. Not a lot, because you need some seam allowance there for strength.
Then turn your pouch or bag right side out and use your fingers or a blunt tool to push out the corners so they’re beautiful.
That’s It!
Just these simple steps, and soon boxed corners will become second nature. You won’t even have to think about it.
Need an Acrylic Template?
We carry ¼-inch and ½-inch acrylic templates in our shop at sewhungryhippie.sbs. And if you’d like to put this technique into practice, check out the Easy Zipper Cases pattern.
Peace, love, sewing.
-Natalie
