FAQ Series: How to BOX an ITH Zipper Bag Tutorial

One of the most requested designs we get is a boxed-bottom bag.  Trust me, if this could be done 100% in the hoop, I would have done it by now!  However, it simply isn't possible.  You can find bunches of complete sewing patterns and free tutorials online if you would like to create this bag completely on your sewing machine. We are going to show you how to use the POP Center Zip Zipper Bag design to create a box zipper pouch. Written tutorial follows, and I have a (formerly) live video in our FB group if you'd like to follow along with a video. 

You can use either of these designs make this bag, depending on which size zippers you prefer to use:

#3 Zipper Center Zip Design

#5 Zipper Center Zip Design

Supplies Needed: 

Recommended supplies in your PDF tutorial

Sewing machine

Lighter (optional)

Clips

Vinyl, Fabric or Ribbon strips for pulls. I added two 1" wide strips of vinyl, folded in half to make a tab, to each end of the zipper during ITH construction. Length of the strip depends on how long you want the finished tabs to be. 

Create your bag according to the instructions from the pattern you chose.  I stitched the POP Center Zip Zipper Bag in size 8x14 (newly added!). Remove it from the hoop, remove stabilizer, and trim around the bag according to the instructions. 

Now here comes a little math... To make a square-ended box, measure the shorter end and divide by 4. This bag is 8", and 8 divided by 4 is 2, so I measured out 2" x 2" squares on each corner of the bag. For the 6x10, my corners are 1.5" x 1.5", and the 5x7 has 1.25" x 1.25" corners. A larger square creates a deeper box, and a smaller square results in a more shallow box.

PRO TIP with lined bags: no matter what pattern you use, make sure to leave yourself room between the liner turning hole opening and the corner cut outs. If the hole opening is a touch too large, close it slightly it on your sewing machine on each end of the opening before you cut out the corners. If you are not lining your bag, this isn't an issue! 

Measure and mark the corners.

Cut out the corners.

Refer back to the zipper bag's instructions. Turn the bag through the liner, close the liner hole, and turn the bag right side out. 

METHOD 1: FRENCH SEAMS. (This is EXTRA FANCY but very easy! Don't be afraid. If you don't want to be extra fancy, skip ahead to Method 2.)

You will lose some width with French seams, so it is important to take the smallest seam allowance possible to close the corners.  

With your bag RIGHT SIDES OUT, take the corners of your bag and pinch them together as shown below. You're flattening the square corners into a straight line for sewing. Match the seams in the center, smooth out to the edges, and clip as needed (my clips are *not* extra fancy). 

Take the bag to your sewing machine, and set the stitch length to a small, secure straight stitch. I set mine at a 3.0 stitch length. Close all 4 corners of the bag by sewing a straight line across each flattened corner square. I use about 1/4" seam allowance if I am NOT doing french seams. If you are going to use French seams, you want a very scant seam allowance! 

Extra, extra fancy tip: Start at the center where the seams meet, lower the needle into the very center of the seams, and sew out to the folded edge. Flip the bag, and repeat from the center to the other folded edge. This method ensures that the center seams don't "scoot" and stay lined up during sewing. 

Once your four corners are closed from the outside, flip the bag inside out--back to where the liner is showing. Take a corner and pinch it flat again, enclosing the previously sewn seam inside the pinch. Clip as needed. 

Sew the flattened corner using a 1/4" seam allowance, which should CATCH the existing seam and conceal it inside the bag. (I used white thread for this tutorial so it would be visible in photographs, but you should use thread and bobbin that closely matches the liner fabric.) Check each corner to make sure the previous seam was completely enclosed by this stitching. 

One end, all sewn up!

Once you have all four corners complete, turn the bag right side out and push out the corners. 

From flat to 3D! MAGIC! 

METHOD 2: 

If you don't care about the fancy French seams, that's ok! We are completing an unlined vinyl bag, but if you chose to line yours, the process is exactly the same for boxing the corners. Create the bag as per the PDF tutorial. If you have a lined bag, turn the bag through the lining hole, close the lining hole, and press it neatly. 

Measure and cut the corners. 

Pinch the corners closed as shown in Method 1. The only difference is that you will be closing up your corners on the INSIDE of your bag, NOT the outside. Match the center seams and clip there, then smooth and clip to the folded corners. Sew the flattened corners with a 1/4" seam allowance. 

If you have lined your bag, the lining will cover the other inside seams of the bag. If you lined the bag with a polyester fabric, you can clean up the edges with the lighter. You can serge or zig zag the raw edges if you prefer, or you could encase them in bias tape. I personally like the vinyl as is, simply neatly trimmed.

Turn the bag right side out and you are done! 

Box all the bags! Come show off your projects, ask questions and chat with us in the POP Facebook group. We can't wait to see what you create.