How to Sew Reinforcement Inseams on Jeans

Reinforced inseams help jeans wear longer.

Reinforcement inseams on jeans appear more difficult to sew than side seams, because of the crotch point. This is where the back and front center seams meet the inside leg seams. A flat-fell reinforcement or self-enclosed seam allows you to cut away some of the bulk created at the crotch. The machine's needle must pierce extra layers of fabric at the crotch without bending or breaking. To sew reinforcement inseams on jeans, use a needle with a thick shaft and sharp point that is made for tough fabric and multiple layers.

Things You'll Need

• Sewing machine
• Size 16/18 needle
• Jeans thread
• Shim
• Straight pins
• Iron
• Scissors

Instructions

Plain Seam

1. Align the inseams with the material turned wrong-sides out and the right sides facing each other. Pin in place using straight pins. Keep the needle from hitting the pins by placing them past the sewing line.

2. Insert the raw hem edged of a jeans leg under the presser foot. Sew the right sides together, using a 5/8-inch seam allowance. Make a continuous sewing line by sewing around the entire length of both legs and the crotch.

3. Sew 3 to 4 inches beyond the material when you reach the end. Hold the thread taut to keep the thread from feeding back into the bobbin.

4. Clip the thread and remove the jeans from the machine. Remove the straight pins and press the seam to one side.

Reinforced Self-enclosed Seam

1. Trim the bottom seam allowance to 1/4 inch around the length of both inseams, including the crotch. This helps reduce the thickness created from heavy, layered fabric.

2. Fold under the upper seam allowance edge to meet the plain stitch line, covering the trimmed seam allowance. Press the fold into place with the iron and pin in place. Stitch along the length of the first seam line.

3. Topstitch 1/8 inch from the fold line closing the fold. This creates three lines along the inseams on the inside of the jeans and two decorative stitching lines on the right side of the jeans.

Tips & Warnings

• The seam may be lower on one side of the presser foot; place the shim under this side to keep the foot stable if it begins to wobble. If you do not have a shim, you can make one from folded jean scraps, the same thickness of the material you are sewing.

• With sewing jeans material, you can use a hammer to flatten thick bulk created where seams intersect. Cover the area with scrap fabric, and lightly pound the thickness. This helps reduce the stiffness, as well.

• Slow the machine down, and hand-turn the wheel if necessary when sewing over thick areas.

References

• Craftstylish; How to Make a Flat-Fell Seam; Shannon Dennis; Dec. 2008
• Sew Neau; How to Make Flat Felled Seams; Shannon Dennis; December 30, 2008
• "Simply the Best Sewing Book": 2001