In this post, we are going to talk about Shoulders! Specifically, how to do a Forward or Backward Shoulder Adjustment for a Set In Sleeve, but I'd like to quickly touch on shoulders in all of their manifestations. I will also give a bit of info for a dolman sleeve at the end.
Shoulders can be broad or narrow, meaning the actual LENGTH of the pattern's shoulder line needs to be longer or shorter to accommodate. Shoulders can be square or sloped, meaning that the ANGLE of the shoulder is more horizontal or vertical than that of the pattern. Shoulders can also be forward or backward, meaning that the shoulder line of the pattern needs to shifted forward or backward to match the line of the wearer.
For a visual explanation of these differences, check out this video: It is entirely possible to need more than one, or all three, shoulder adjustments.
If you would like to follow along with me on video, you can find us over on YouTube:
A forward or backward shoulder adjustment is focusing on where the shoulder seam lies along the top of your shoulder. It should line up with your acromion process (anatomy lesson!). That's the little bone that sticks up at the end of your collar bone, right before the crease when you raise your arm. If the shoulder seam of your garment sits behind that little bone, your garment likely wants to pull backwards. You will need a forward shoulder adjustment to bring the seam inline. This is the most common of the two. The opposite (seam sits in front of the little bone), is where your garment likely falls forward, and you will need a backward shoulder adjustment.
One thing worth noting: if it seems like you are adding a lot to your forward shoulder adjustment, it could be because, or in conjunction with, a high round back. This is where, at the base of the neck, the back is rounded and the head tilts forward. I will be writing a separate post for this and will link it here when complete.
You will need the front and back bodice pieces, as well as your sleeve piece. First, you need to determine how much you will want to move the seam. A muslin is the best way to determine this, but it shouldn't be much. If it is more than 1/2" or so, consider my previous statement about the high round back.
FORWARD SHOULDER ADJUSTMENT:
We're going to start with the front bodice. Let's say that we've determined we need to move the seam forward by 1/4". Using a straight ruler, measure 1/4" down from the shoulder line. Cut along that line to remove the excess, and that is your front bodice adjusted.
Next, we have to compensate for that amount you removed from the front bodice. Draw a horizontal line just below the neckline. Cut on that line and spread the top away from the bottom by the same amount you shortened the front bodice. Redraw the center back, and gently curve the armscye.
One last thing before we move on to the sleeve. You'll notice that, by doing this adjustment, you've lengthened the center back as well as shortened the neckline. You will need to compensate for the center back by shortening at the waistline and tapering back to zero at the side seam. And the neckline will need to be dropped by the amount you removed and redrawn.
Lastly, we need to adjust the sleeve notch so that it matches up with the new shoulder line. Draw a horizontal line parallel to the sleeve hem (or perpendicular to the grainline), approximately halfway down the sleeve cap. Cut on that line.
We will now move the sleeve cap FORWARD by the same amount that you moved the shoulder seam line (in our case, 1/4"). Gently redraw the sleeve cap curves.
That's it! You're all done!
BACKWARD SHOULDER ADJUSTMENT:
We're going to start with the front bodice. Let's say that we've determined we need to move the seam back by 1/4". Using a straight ruler, measure down from the shoulder line by an inch or so. Cut along that line.
Move the top part away from the bottom part by 1/4" (or whatever amount you've chosen). Place paper behind the bodice and redraw the neckline and armscye.
For the back bodice, we will need to do the exact opposite by removing the amount you added to the front bodice. Draw a horizontal line just below the neckline. Cut on that line.
Overlap the over the bottom by the same amount you shortened the front bodice. Redraw the center back, and gently curve the armscye.
One last thing before we move on to the sleeve. You'll notice that, by doing this adjustment, you've shortened the center back as well as lengthened the neckline. You will need to compensate for the center back by lengthening at the waistline and tapering back to zero at the side seam. And the neckline will need to rise by the amount you added, and redrawn.
Lastly, we need to adjust the sleeve notch so that it matches up with the new shoulder line. Draw a horizontal line parallel to the sleeve hem (or perpendicular to the grainline), approximately halfway down the sleeve cap. Cut on that line.
We will now move the sleeve cap BACKWARD by the same amount that you moved the shoulder seam line (in our case, 1/4"). Gently redraw the sleeve cap curves.
That's it! You're all done!
NOTES ON A DOLMAN SLEEVE: If your dolman pattern is a two-piece pattern (the long sleeve is sewn on to the short sleeve), you can do this adjustment in the same manner as above. Because the sleeve is cut on the fold and there is no 'cap', aligning the under arm seams will work no matter if you adjust the shoulder seam forward or backward.
For a one piece dolman, the shoulder seam runs down the entire length of the shoulder and sleeve. You will either need to move the entire seam.
Here's a BLOG post that has a bit more information on the difference in these dolman sleeves.
Happy Making!
Rachelle