How to Alter Shoulder Seams on a Jacket

Tissue-fitting your jacket before you sew will eliminate any fit problems in the shoulders.

A jacket has to fit well across the shoulders in order to hang right and look good. Most people aren't exactly the same size as the standard mannequins that sewing patterns are made to fit. But you can learn about common fitting problems and how to fix them on the jacket pattern, before you cut out the fabric. Then you can fine-tune the fit with the fabric before making the final seam.

Things You'll Need

• Sewing pattern
• Tracing paper
• Tape
• Pins
• Markers

Instructions

Tissue Fitting

1. Trace the front and back pieces of the jacket pattern along the lines for your size. Cut out the tracing paper patterns, and put tape along the seam lines. Pin the front and back pieces together at the shoulders and side seams. Try on the paper pattern.

2. Look at the fit of the paper pattern in the mirror, to check the shoulder width. The shoulder seam may extend too far out past the pivot point at the top of your arm. If you wish to bring the shoulder seam in some, mark on the paper how you will draw the arm hole deeper into the shoulder seam. If you have narrow shoulders, this may be as much as 1 inch on both sides. For wide shoulders, you may need to add some tissue to the outside edge of the shoulder.

3. Check the angle of the seam on the shoulders. If you have square shoulders, you will see diagonal wrinkles pointing toward the shoulders, and in the back, horizontal wrinkles at the base of the neck. Similarly, your shoulders may slope more than the pattern does. Alter the paper pattern by raising the shoulder seam at the sleeve edge for square shoulders, and lowering it for sloping shoulders. Redraw the seam line with the marker, pin along the new seam line, and try on again.

4. Check to see that the shoulder seam runs from the base of your neck to the pivot point on your shoulder. If it falls much behind the pivot point, you may need to alter the seam for forward shoulders. Drop the seam line on the front piece outer edge, and raise it on the back piece outer edge.

Fitting the Fabric Pieces

1. Take off the paper pattern and unpin the pieces. Pin the newly altered front and back pieces to the fabric and cut it out, leaving extra seam allowances for more adjustments before sewing. Transfer the new markings to the fabric pieces.

2. Pin the fabric front and back pieces together at the shoulders and side seams, wrong sides together. Try on the pinned-together garment with the pinned seams to the outside, and check the fit at the shoulders again. Move the pins around, until the seam is in the right place and the jacket hangs nicely on the shoulders. Mark the seam lines with a washable marker on the inside of the garment.

3. Pin the front to the back along the seam line, right-sides together, and baste. Press the seam open. Try on the jacket one more time before the permanent seam is put in. If the fit looks right, there are no wrinkles along the front or back, and the top of the arm hole fits the shoulder at the right spot, you can sew the final seam with confidence that you have it right.

Tips & Warnings

• If you do a lot of sewing, it's a good idea to make a basic fitting pattern -- sometimes called a fitting shell -- in your size. This way, you can see how your body varies from the standard sizing used by pattern companies, and you will know exactly how to alter every pattern you sew.

References

• "Fit for Real People"; Palmer et al; 2006