The best part of finding a knit T-shirt pattern that fits well is personalizing it. You can sew a T-shirt with stripes, solids or whatever print that you want.
But sometimes, sewing T-shirts with the exact same cut and fit can get a little boring. So why not shake things up in a big way by changing the neckline? Though it may sound intimidating, changing the neckline is actually quite simple.
We’ll start here, with a knit T-shirt that has a scoop neckline.
One of my favorite T-shirt patterns included a piece for this scoop neck, but not one for a crew neck style. By measuring the circumference of any neck opening you design, you can create a new neckband that fits. Let’s take a look at the pattern piece for the front of the top.
I first traced the pattern piece onto paper to make it easier to see. The blue outline shows the original scoop neckline, and the red shows the new higher neckline.
I copied the shape of the new neckline from an existing T-shirt to determine how much to raise it. Note that if you’re going to make changes in your knit T-shirt pattern, it’s helpful to trace the pattern pieces and then make all your changes on the copies, retaining your original pattern for future use. Feel free to mark and measure on your copies as I have done here.
Step 1: Mark the stitching lines
Once you’ve drawn in your new neckline, mark the stitch lines. That is the dotted line, marked on the 5/8″ seam allowance. I stuck with 5/8″ for this example, but you can customize your neckline seam allowance to whatever you prefer. A slightly narrower seam allowance of ¾” or 3/8″ works best for most patterns.
On this T-shirt I’m not going to change the back neckline, but I copied that pattern piece as well.
Step 2: Measure the stitching line
Measure the length of the stitching line on the new neckline. To measure this curved line, you can place your tape measure on its side as shown. If you have a flexible ruler you can use that instead. Measure from the center front to the shoulder seam. This one measures 6¾”.
Step 3: Calculate the new neck opening
Here are the measurements for the neck opening: The front stitching line is 6¾” and the back is 4¾”. (Even if you don’t change the shape of the back neckline, you still need to measure it for the calculation.)
Then, add the front and back measurements together and double that number. It’s doubled for the full circumference of the neckline, since we only measured half on the pattern pieces since they are cut on the fold.
For my T-shirt, we have: (6¾” + 4¾”) = 11½” x 2 = 23″
Step 4: Calculate the neckband size
Now you’ll need to do the calculation for the neckband. We want the neckband to be a bit smaller than the neck opening, as the neckband is stretched slightly to pull the opening close to the body.
Use 7/8 of the total circumference of the neck opening that you found in the previous step. So, I multiplied 23″ x 0.875 = 20-1/8″
I chose to drop that fraction and use a final measurement 20 inches for the new neckband. This includes the seam allowance to join the neckband seam.
Step 5: Cut the neckband
Cut your new neckband to the length of your calculation and whatever width you want. You can even use the original neckband from the pattern and just change the length.
Seam the neckband together as you normally would, then attach it to the neck opening. I like to find the center point and pin that to the center front, put the seam at the center back and then ease the neck opening to the band on either side. I also baste the neckband on to see if the fit is accurate, as every knit fabric behaves differently. Sometimes the neckband needs to be a bit smaller to create a snug fit around the neck.
Same pattern — different necklines. Now your pattern library just got bigger without storing any more patterns.