This is the step whereby the flange is turned into a skeleton, supporting the tailored cloth grocery bag. This step reinforces the six edges and four corners of the bags: front panel side, bottom, and side and back panel side, bottom, and side.
Measure Twice, Cut OnceMeasure down 2 inches from the top edge and draw a line on each of the four flanges, perpendicular from the stitch line to the outer edge. This measurement is the same whether you cut 13 by 15 inch panels or 14 by 16 inch panels.
Snip out a triangle of cloth on each of the four flanges, coming within a few threads of the stitch line. The triangle you cut from the flange will let you fold down the top of the bag while minimizing bulky seams.
The easiest way to cut the flange triangle is to fold over the flange with the marked line facing up and then cut a wedge from the stitch line to the outer edge. This way you don’t accidentally cut through the stitch line.
TIME-SAVING TIP: It is quicker (fewer hand motions) to draw the flange lines on all of your grocery bags first, then make all the triangular cuts rather than marking and snipping each flange in turn.
When you’re done, work your way through all the bags, sewing the flanges down.
Sewing Down the Flange
The flange is sewn down so the upper part (above the cutout) is sewn to the panel. The lower part of the flange (from cutout to cutout) is sewn to the gusset. When you reach the second cutout, the upper portion is again sewn to the panel.
It works best to align the flange-to-gusset seam so that the stitch line is at the far side of the presser foot. That is, you want the presser foot resting entirely upon the flange when sewing it to the gusset. This won’t happen when sewing the small upper portions to the panels.
I don’t normally iron the flanges in place before sewing them. I press them down in place with my fingers as I go. Adding an ironing step for the first few bags may make it easier for you.Set the needle to its normal, left position and set the stitch to .4mm to secure the seam. Position the bag with the gusset to the left of the needle and the panel to the right. Press the upper portion of the flange (above the triangle cut out) down on the panel. Stitch down the flange about ¼-inch to secure the seam, then adjust your stitch length to 3mm or thereabouts.
When you reach the cutout triangle, lift the presser foot and pivot the bag so you can stitch down the cut edge, crossing over across the seam line, sewing the second part of the cut edge onto the gusset, pressing down the flange onto the gusset. Pivot the needle again at the end of the raw edge and sew the flange to the gusset, following the shape of the bag.
As you stitch down the flange along the side seam, keep the fabric taut.
When you are an inch away from the corner, adjust the stitch length to 1mm to reinforce the corner. Continue sewing the flange to the gusset up to the corner, adjusting as needed to keep both flange and gusset smooth and wrinkle-free.
Pivot at the corner and sew another inch with a 1mm stitch length. Lengthen your stitch back to 3mm or thereabouts, continue to the next corner, and repeat the corner sewing procedure.
Continue sewing the flange to the gusset and when you reach the cutout portion, sew across the seam line, and continue up the panel side. Shorten your stitch to .4mm to secure the seam line when you reach the top of the bag.
Flip the bag over and repeat the procedure on the back panel side, securing the flange to the panel above the cut, to the gusset for the remainder of the flange (side, corner, bottom, corner, side) and above the cut, secure the flange to the panel.
Repeat for all the bags. As you finish each bag, lay it flat with the gusset bottom folded between the front and back panel.
(This post is a draft from the upcoming book “Sewing Cloth Grocery Bags.” A complete list of the posts can be found here.)