You’ve sewn the perfect t-shirt. The fit is great, the neckline is smooth. But then you get to the hem.
As you stitch around the bottom, the fabric starts to ripple. By the time you finish, the hem looks like a piece of bacon—wavy, stretched out, and completely unprofessional. You try ironing it, but the wave won’t go away.
Most sewers blame their sewing machine or their lack of skill. But in the Fair Fit Method, we know this is usually a Geometry Problem, not a sewing problem.
When you sew a curved hem (which most shirts have), you are cutting across the grain of the fabric. This exposes the “Bias”—the stretchiest part of the textile. If you don’t stabilize that bias before you stitch, you will stretch it permanently.
Here is the logic behind the “Bacon Hem” and the 3 studio techniques to fix it.
1. The Physics: You Are Fighting the “Feed Dogs”
Your sewing machine has metal teeth (feed dogs) on the bottom that pull the fabric through. But the standard presser foot on top is smooth metal.
- The Conflict: The bottom layer of fabric is being pulled faster than the top layer.
- The Result: This friction stretches the fabric as it passes under the needle. On a stable cotton, you won’t notice. But on a stretchy knit or a bias-cut skirt, that stretch gets “baked in” by the thread.
The Fix: The Walking Foot
If you don’t own a Walking Foot (or Even Feed Foot), you need one. It adds a set of “teeth” to the top of the fabric, so both layers move at the exact same speed. It is the single best investment for professional hems.
Master Your Tools: Understanding your machine mechanics is the first step to professional results. In our Beginner’s Sewing Online Course, we dedicate entire modules to mastering these tools so you stop fighting your machine and start controlling it.
2. Chemical Engineering: Stabilize Before You Stitch
In a professional studio, we rarely rely on the machine alone. We use stabilizers.
If the fabric wants to stretch, we force it to stay still using a temporary structure.
The Fix: Fusible Hem Tape
Before you sew, iron a strip of double-sided fusible hem tape (like Steam-A-Seam) between the hem layers.
- Iron the hem in place. The glue melts and fuses the layers together.
- Now the fabric is stiff and stable.
- Stitch over it. The needle goes through the glue, and the fabric cannot stretch because it is glued shut.
This is how industry hems look so flat. They are engineered to be rigid during the sewing process.
3. The “Pattern Hacking” Connection (Curved Hems)
Sometimes, the wave happens because of how you altered the pattern.
If you decided to add more “flare” to a skirt or shirt by swinging the side seams out, you have changed the geometry of the hem. You have turned a straight grain hem into a Bias Hem.
The more curved the hem, the more it will stretch.
If you are altering patterns without understanding the geometry of the grainline, you will constantly fight these distortion issues. You can’t just change the shape; you have to understand how that change affects the fabric’s behavior.
This is the core of Pattern Hacking—learning how to manipulate the structure of a pattern without breaking its integrity.
Learn the Logic: Don’t just guess at alterations. Our Pattern Hacking Online Class teaches you the industry-standard rules for modifying patterns so your design changes don’t ruin the structural integrity of your garment.
Summary: Stop Pulling!
The number one habit to break? Pulling the fabric behind the needle.
When you pull the fabric to “help” it through the machine, you are manually creating the wave. Let the feed dogs do the work. Your hands are only there to guide, not to drive.
Trust the machine, stabilize your bias, and your hems will lie flat every time.
Ready to stop guessing and start designing? Explore our full Online Curriculum to find the right course for your skill level.
Online course · $75
Learn to sew from the very first stitch
Beginner Sewing walks you through setting up and controlling your machine, the core techniques nearly every project uses, and your first finished projects. Work at your own pace from home.
See Beginner Sewing Not sure where to start? Find your starting point
About Andrea Eastin
Andrea Eastin is a fashion designer, pattern maker, and the creator of the Fair Fit Method. With a background in professional tailoring and design education, Andrea teaches sewers how to move beyond “home sewing” instructions and adopt the logic, techniques, and creative freedom of the design studio. She believes that fit is not a mystery—it’s a process—and that everyone deserves clothes that honor their unique body shape.