How to Master Curves on the Serger: Inside and Outside Curves

Serging curves can feel challenging at first because the fabric is constantly changing direction while the serger is trimming and stitching at the same time. In our Serging With the Girlfriends video, we cover a clear approach for handling curves so your seams stay clean, even, and controlled.

Why curves behave differently on a serger

When you move into a curve, you’re balancing a few things at once:

• Consistent seam allowance as the knife trims the edge

• Even feeding (especially on knits)

• Gentle guiding—without stretching or forcing the fabric

• Maintaining a smooth stitched edge around changing angles

The goal is to let the serger do the work and simply guide the fabric steadily through the curve.

The most important principle: guide, don’t pull

A common cause of waviness and uneven trimming is pulling the fabric to “make” it turn. Instead:

• Keep a light touch

• Steer the fabric gradually through the curve

• Focus on keeping the fabric edge aligned at the blade/seam guide

Small adjustments are more effective than one big turn.

Serging an outside curve (convex)

Outside curves include shapes like rounded edges, curved hems, and many coaster or pouch corners.

Steps:

1. Slow down before the curve begins.

2. Keep the fabric edge aligned with your usual guide so the knife trims consistently.

3. Use your hands to rotate the fabric gradually as you serge—think in small movements.

4. For tighter curves, pause briefly as needed (needle down if your machine allows) to reposition your hands and keep control.

Helpful note (especially for knits): If your edge starts to wave, your differential feed may need adjustment. Testing on scraps makes this quick and low-stress.

Serging an inside curve (concave)

Inside curves include armholes, necklines, and scooped shapes. These usually require one extra step: clipping the seam allowance so the fabric can spread and lie flat as it turns.

Steps:

1. Before serging, make small clips into the seam allowance along the inside curve.

   • Clip up to the seam allowance, but do not cut through the stitch line.

2. Serge slowly, keeping the fabric edge aligned and letting the feed move the fabric.

3. As the clipped area feeds under the presser foot, keep the fabric flat so it doesn’t bunch.

Tip: Tighter curves typically need more frequent clips for a smoother result.

Quick troubleshooting

Wavy edge

• Avoid pulling the fabric

• Adjust differential feed (especially with knits)

• Slow down and guide more gently

Uneven seam allowance

• Watch the fabric edge at the knife/guide

• Keep steady alignment and reduce speed on tight curves

Puckering

• Re-check tension on a scrap

• Make sure you’re not pushing fabric into the blade area

• Confirm you’re using the right needle/thread for the fabric type

A simple way to practice

Cut a “curve sampler” from scrap fabric with a mix of:

• gentle outside curves

• tight outside curves

• gentle inside curves

• tight inside curves

Serging several in a row builds the hand control quickly and helps you see what settings changes make the biggest difference.

Come hang out in our Serger-Obsessed Corner of the Internet

If you want serger tips, troubleshooting help, settings chats, project inspo, and that “oh good, it’s not just me” feeling—join our private Facebook group all about sergers!

Ready to bring home a serger (or upgrade)?

At My Girlfriend’s Quilt Shoppe, we know a serger is the secret to professional-looking seams, flawless finishes, and stretch-friendly stitches. That’s why we carry trusted brands like Brother and Baby Lock, offering everything from beginner-friendly models to advanced sergers with cover stitch options. Whether you’re sewing garments, home décor, or quilting accents, we’ll help you choose the serger that takes your stitching to the next level.

You can shop sergers right on our website—beginner-friendly options all the way up to feature-packed dream machines.

Watch the full video tutorial

If you’d like to see these curve techniques in action, watch the full video tutorial—it’s much easier to understand when you can see the hand placement, pacing, and how the fabric is guided through each curve. Follow along with your own scrap fabric as you watch so you can practice in real time!

Happy serging, friends!