There's nothing like finding a T-shirt pattern that just fits really well. But even we get sick of the same old T shape, so why not try personalizing it with a different neckline? It's dangerously simple to do, and will help shake up your wardrobe in a big way.
Let's start with a classic: the scoop neck. By measuring the circumference of any neck opening you design, you can create a new neckband that fits like a dream. Here's a look at the pattern piece for the front of the shirt.
I traced the pattern piece onto paper to make it easier to see. The original scoop neckline is in blue, and the new higher neckline is in red.
I just copied the shape of the new neckline from an existing T-shirt to determine how much to raise it. Just know that if you're going to make changes in your knit T-shirt pattern, it'll help to trace the pattern pieces and then make all your changes on the copies. That way you can keep your original pattern for future use without having to start from scratch each time you want to experiment.
Step 1: Mark the stitching lines
Once you've drawn your new neckline, mark the stitch lines — that's the dotted line you see here, marked on the ⅝" seam allowance. I used ⅝" for this example, but feel free to customize however you'd like. A slightly narrower seam allowance of ¾" or ⅜" works great for most patterns.
On this shirt, I won't bother changing the back neckline, but I did copy that pattern piece as well.
Step 2: Measure the stitching line
Measure the length of the stitching line on the new neckline by placing your tape measure on its side or using a flexible ruler. Then measure from the center front to the shoulder seam. This one measures 6¾".
Step 3: Calculate the new neck opening
Now we have our new measurements: The front stitching line is 6¾" and the back is 4¾". (Even if you don't change the shape of the back neckline, you'll still need to measure it for the calculation.)
Okay, stick with us. We promise the math-y parts are almost over. Add the front and back measurements together and double that number. You double it to get the full circumference of the neckline since we only measured half on the pattern pieces.
For my T-shirt, we have: (6 ¾" + 4 ¾") = 11 ½" x 2 = 23"
Step 4: Calculate the neckband size
We want the neckband to be a bit smaller than the neck opening since it's stretched slightly to pull the opening close to the body.
Use ⅞ of the total circumference of the neck opening that you found in the step 3. For mine, I multiplied 23" x 0.875 = 20⅛"
To keep it clean, I dropped that goofy little fraction and will use 20" for the new neckband. That includes the seam allowance to join the neckband seam.
Step 5: Cut the neckband
Cut your new neckband to the length you calculated and whatever width your heart desires. No pressure to get crazy here — you can use the original neckband from the pattern and just change the length.
Time to wrap up! Seam the neckband together just like you normally would, then attach it to the neck opening. I start by finding the center point and pinning that to the center front. Then I put the seam at the center back and ease the neck opening to the band on either side. Pro tip: Baste the neckband on to see if the fit is accurate; every fabric behaves a little differently! Make any adjustments needed and then prepare to show some neck.