You can adjust shoulder width on a sewing pattern by narrowing or widening the shoulder seam while reshaping the armhole to maintain a smooth fit. For adjustments up to 1.5 cm (⅝ inch), the change can be made at the shoulder edge; larger adjustments require a more substantial pattern alteration.
In this guide, you’ll learn how to tell whether you need a narrow or wide shoulder adjustment, how to make minor and major adjustments, and how to check the armhole and sleeve after altering your pattern. These fitting techniques can also be useful when working with Winslet’s sewing patterns and adapting a pattern to better suit your measurements.
How Do You Know If You Need a Shoulder Adjustment?
You may need a narrow shoulder adjustment if the shoulder seam extends beyond your shoulder. A wide shoulder adjustment may be needed if the garment feels tight across the top of the arm or you see pull lines in this area.
Ideally, make a sample garment before altering your pattern so you can assess the fit on your body.
The shoulder seam should sit in line with the crease of your armpit and feel comfortable. Check the position of the shoulder seam rather than relying only on how the garment feels.
What does a narrow shoulder adjustment fix?
A narrow shoulder adjustment brings the shoulder seam closer to the body when the pattern's shoulder is too wide.
What does a wide shoulder adjustment fix?
A wide shoulder adjustment extends the shoulder seam when the pattern does not provide enough width across the shoulder.
How Much Should You Adjust the Shoulder?
For an adjustment of up to 1.5 cm (⅝ inch), you can make a minor adjustment directly at the end of the shoulder. For adjustments larger than 1.5 cm, a more substantial adjustment is recommended.
The adjustment amount should be based on the fit of your sample garment. Once you know how much needs to be removed or added, you can choose the appropriate method.
How to Make a Minor Shoulder Adjustment
A minor shoulder adjustment is suitable when you need to remove or add up to 1.5 cm (⅝ inch) at the shoulder.
For a narrow shoulder adjustment
To narrow the shoulder, measure inward from the existing shoulder edge by the amount you need to remove.
For a wide shoulder adjustment
To widen the shoulder, measure outward from the existing shoulder edge by the amount you need to add.
For example, if you need to add 1 cm (⅜ inch) to the shoulder, mark the new shoulder edge 1 cm beyond the original position.
Step-by-step
- Mark the new shoulder position. Measure inward for a narrow adjustment or outward for a wide adjustment by the required amount.
- Blend the new shoulder into the armhole. Use a French curve to create a smooth transition, aiming to blend the new shoulder position into approximately the midpoint of the armhole.
- Repeat the adjustment on the other bodice piece. Make the same adjustment to both the front and back.
- Check the shoulder connection. Place the front and back together and make sure the shoulder seams match.
- Keep the shoulder end straight. The shoulder should remain straight for approximately 2 cm (¾ inch) from the end rather than forming a V-shape.
- Check the stitching line. Drawing the stitching line onto the pattern can make it easier to create a clean connection between the shoulder and armhole.
How to Make a Major Shoulder Adjustment
For an adjustment larger than 1.5 cm (⅝ inch), use a slash-and-shift method to remove or add more width through the shoulder.
This method uses vertical and horizontal lines to create a movable section of the pattern. The section can then be shifted toward the centre front or centre back for a narrow shoulder or toward the side seam for a wide shoulder.
Step-by-step
- Draw a vertical line through the shoulder. Place it approximately in the middle of the shoulder, parallel to the centre front or centre back and the grainline.
- Draw a horizontal line through the armhole. Position it approximately halfway down the armhole, at a right angle to the centre front, centre back or grainline.
- Cut along the lines. Cut the pattern so that the section containing the shoulder corner can move while remaining connected along the horizontal line.
- Mark the adjustment amount. Clearly mark how much you need to remove or add.
- Shift the shoulder section. For a narrow shoulder, move the cut section toward the centre front or centre back. For a wide shoulder, move it toward the side seam.
- Tape the section in place. Once the required amount has been removed or added, secure the pattern.
- Repeat on the other bodice piece. Make the same adjustment to the back if you adjusted the front, ensuring the shoulder width remains consistent.
- Reconnect the shoulder seam. Draw a straight line from where the shoulder meets the neckline to the new shoulder edge.
- Recurve the armhole. Use a French curve to create a smooth transition from the new shoulder position into the armhole.
Example: A 2.5 cm narrow shoulder adjustment
If you need to remove 2.5 cm (1 inch) from the shoulder, mark a new vertical line 2.5 cm toward the centre front or centre back. Slide the cut shoulder section along the horizontal line until it reaches this new line, then tape it in place.
Repeat the same 2.5 cm adjustment on the other bodice piece.
How Should You Reshape the Armhole?
The armhole needs to be redrawn after a shoulder adjustment so that it has a smooth, natural curve.
The front and back armholes should not be treated as identical shapes. The front armhole is generally a deeper, smoother curve, while the back starts straighter and finishes with a slight hook shape.
How to recurve the armhole
- Mark the stitching line on both patterns.
- Fold the seam allowance under on one pattern piece.
- Place the front and back together along the stitching line at the shoulder.
- Use a French curve to connect the new shoulder position to approximately the midpoint of the armhole.
- Create a smooth curve that follows the general shape of the original armhole.
- If a French curve does not give you a suitable shape, particularly on the back armhole, sketch the curve by hand while maintaining a similar shape to the original.
The goal is not to completely redraw the armhole. The new curve should transition naturally between the altered shoulder and the existing armhole.
Do You Need to Adjust the Sleeve?
You should check the sleeve after changing the shoulder width because the armhole measurement may have changed.
Measure the stitching line of the adjusted armhole separately for the front and back. A tape measure placed on its edge can be used to measure the curved stitching line accurately.
If you have the original pattern, compare the new armhole measurement with the original. This shows how much the adjustment has changed the armhole and helps you determine whether the sleeve also needs attention.
For a basic bodice, the sleeve stitching line is generally aimed to be about 1 cm (⅜ inch) larger than the total armhole, divided between the front and back:
- Front sleeve: about 5 mm (¼ inch) larger than the front armhole
- Back sleeve: about 5 mm (¼ inch) larger than the back armhole
As long as the sleeve is the same size as, or larger than, the armhole, the sleeve measurement is considered workable according to this method.
What Should You Check After a Shoulder Adjustment?
Always make a sample after finalising the pattern and check the fit again.
Before sewing the sample, check that:
- The front and back shoulder adjustments are the same.
- The shoulder seams match.
- The shoulder remains straight at the end rather than forming a V-shape.
- The armhole has a smooth curve.
- The front and back armhole measurements have been checked separately.
- The sleeve still corresponds appropriately with the adjusted armhole.
If you measured the original armhole before making the adjustment, comparing it with the altered measurement can help you understand how much the armhole has changed.
If you'd like to see these narrow and wide shoulder adjustments demonstrated step by step, you can watch the video below.
Get a Better Fit From Your Sewing Pattern
A shoulder adjustment can be a relatively small pattern change, but checking the shoulder position, armhole shape and sleeve measurements helps ensure the alteration works as intended. Always make a sample after adjusting the pattern so you can check the final fit before cutting your garment in your main fabric.
When you're ready for your next project, explore Winslet’s sewing pattern collections and use these fitting techniques to adapt your chosen pattern to your measurements.
FAQs
How do I know if I need a narrow shoulder adjustment?
If the shoulder seam hangs beyond your shoulder, you may need to narrow the shoulder. Make a sample first so you can assess exactly where the shoulder seam sits.
How do I know if I need a wide shoulder adjustment?
If you notice pull lines or the garment feels tight over the top of your arm, you may need a wide shoulder adjustment.
How much can I adjust at the shoulder without using the major adjustment method?
For an adjustment of up to 1.5 cm (⅝ inch), you can make the change directly at the shoulder edge.
What if I need to change the shoulder by more than 1.5 cm?
For adjustments larger than 1.5 cm (⅝ inch), use the major adjustment method by creating vertical and horizontal lines, moving the shoulder section, reconnecting the shoulder seam and reshaping the armhole.
Do I need to adjust both the front and back?
Yes. The same shoulder adjustment should be made to both the front and back so the shoulder seams continue to match.
Do I need to change the sleeve?
Not necessarily. First measure the adjusted armhole and compare it with the original measurement and the sleeve. Ideally, the armhole should not change substantially, but checking the measurements will show whether the sleeve needs attention.
