How to Sew Curves: Clipping and Notching Explained
@TashaCouldMakeThat
@Giorgia Costumes
@Minerva
Step-by-Step Instructions:
Sewing a curved seam is only half the battle. Because fabric naturally wants to lay flat, forcing a seam allowance to bend inside a garment will cause severe puckering or bulky lumps. The secret to beautifully smooth necklines and armholes is clipping and notching the seam allowance.
Materials Needed:
- Fabric pieces pinned along a curve
- Sewing machine
- Small, sharp embroidery scissors or thread snips
- Pinking shears (optional)
- Iron and pressing mat
Tips for Success:
- Shorten your stitch length slightly (to about 2.0mm) when sewing curves. Smaller stitches navigate the bend smoother and create a stronger seam that resists tearing when you clip it.
- Work in a well-lit area! Accidentally snipping your stitches is a frustrating setback.
1. Sew the Curve
- Sew your curved seam carefully, taking your time to guide the fabric evenly along the seam allowance line. Do not stretch the curve as it goes under the presser foot.
2. Identify the Curve Type
- Look at the seam allowance you just created. Is it an inward (concave) curve like a neckline? Or is it an outward (convex) curve like the rounded edge of a collar or pocket?
3. Clipping (For Inward Curves)
- When turning an inward curve right-side out, the seam allowance is forced to stretch. To relieve this tension, take your small scissors and make straight cuts (clips) into the seam allowance perpendicular to the stitches. Space the clips about 1/2 inch apart. Cut as close to the stitching line as possible (about 1/16″) without cutting the thread!
4. Notching (For Outward Curves)
- When turning an outward curve right-side out, the seam allowance is forced to compress, creating bulky lumps. To remove this bulk, cut tiny “V” shaped wedges (notches) out of the seam allowance along the curve. Again, cut close to the stitches without snipping them. (Pro tip: You can use pinking shears to cut zigzag notches instantly!)
5. Grade the Seam (Optional)
- If your fabric is thick, you may want to “grade” the seam allowance to reduce even more bulk. Trim one layer of the seam allowance to be shorter than the other. This prevents a thick ridge from showing on the outside of the garment.
6. Press the Curve
- Turn your fabric right-side out. The inward curves should easily spread open, and the outward curves should fold back smoothly without bunching. Press the curve flat with an iron. If you have a tailor’s ham, press the fabric over the rounded surface of the ham for a perfect, professional finish.
Top FAQs for Clipping & Notching Curves:
What is the difference between clipping and notching? +
Clipping means making straight snips into the seam allowance to allow the fabric to stretch and open up (used for inward/concave curves). Notching means cutting out tiny V-shaped wedges to remove excess fabric so it doesn’t bunch up (used for outward/convex curves).
How close to the stitching line should I cut? +
You want to get as close to the stitching line as you safely can—usually about 1/16 to 1/8 of an inch away. If you don’t cut close enough, the fabric will still pull and look lumpy on the outside.
Why does my curved seam still look bumpy after turning? +
If the curve is still bumpy or puckered, you likely didn’t make enough cuts, or your cuts didn’t go close enough to the stitching line. Turn the project back inside out and add a few more strategic clips or deeper notches.
What happens if I accidentally cut my stitches? +
Don’t panic! It happens to everyone. Simply take the project back to the sewing machine and sew a new, short line of stitching just slightly inside the original broken seam line (about 1/8 inch deeper) to secure the hole, tapering it back into the original seam.
Can I use pinking shears instead of cutting notches by hand? +
Yes, absolutely! Pinking shears are designed to cut zigzag edges, which automatically removes tiny triangles of fabric. Trimming an outward curve with pinking shears is a fantastic, time-saving hack for notching.
Do I need to clip curves if I am using a serger? +
Usually not. Serged seams are cut so narrow (about 1/4 inch) that they inherently have very little bulk. However, for extremely tight concave curves (like deep necklines), standard sewing and clipping will yield a much flatter, cleaner finish than a serger.
