How to Sew a Notched Jacket Lapel
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Ready-to-wear suits all have something in common: smooth lapels with nice, crisp edges. Achieving that professional finish can get a little tricky because one tiny detail can cause big sewing trouble-the notch where the collar joins the lapel.
There’s no need for frustration once you know this technique for achieving a flawless lapel. Manufacturers long ago solved this challenging part of jacket construction, and you can use their solution easily at home. The secret involves a bit of prep work on your pattern pieces and a careful, but simple, seven-step process to stitch, clip, and press for lapel perfection. Through this process, you’ll also discover how understitching can enhance edge seams and sharpen corners-sewing information that will improve your results in a variety of garments.
Sharpen Your Collar Corners
First, prepare and sew most of your jacket seams. Interface, staystitch, tape the roll line (where the lapel folds back and the facing turns to the outside), and join the shoulder seams as your pattern instructs. Then proceed with the steps described here.
Interface and Assemble the Collar
1. Interface the undercollar. If your undercollar pattern is two pieces, interface both and join them at the center back. Trim the center-back seam allowances to 3⁄8 inch. Fuse tailor’s canvas (minus seam allowances) to the undercollar. Pin the undercollar around a tailor’s ham, and steam it to set the shape. When it’s completely dry, sew the upper collar to the undercollar along the top edge only with right sides together.
2. Trim and understitch the collar’s upper edge, then sew the corner seams. Trim the sewn seam allowances to 1/4 inch, then fold them toward the undercollar and understitch (see “Understitching Secrets” below). Then, sew the collar corners with right sides together. The seams will cross the folded and understitched end seam allowances of the collar’s upper edge.
Trim and Turn the Collar Corners
1. Trim the end seam allowances to 1/4 inch. Hold the scissors at an angle to bevel the cut edge so the upper collar has the slightly wider seam allowance. Clip the corners to remove bulk.
2. Prepare to turn the collar right side out. Fold and press the end seam allowances to the collar’s underside. Hold the seam allowances in place with your finger and turn the collar right side out.
Cut the Excess ‘Turn of Cloth’
When the turned collar is folded lengthwise on the roll line, the neck edge seam allowance will extend beyond the upper-collar neck edge because of the thickness of the folded layers. This is called “turn of cloth,” and it will be a different amount for fabrics of different thicknesses.
1. Fold the completed collar along its roll line. The undercollar seam allowance will extend beyond the upper-collar seam allowance. Pin the collar layers together, maintaining this offset.
2. Trim the undercollar edge to match the upper-collar edge. Later, when you stitch the neckline seams, follow the trimmed edges exactly to maintain the turn of cloth you established here.
Stitch and Clip to Perfection
Once you have interfaced, sewn, and trimmed the collar, it’s time to combine it with your jacket. Clothing manufacturers use a similar method to achieve polished results.
1. Attach the assembled undercollar to the jacket neck edge. Match notches and marks. Stitch as close as possible (to within at least 1/4 inch) to each end of the collar.
2. Attach the jacket facing. Pin the facing (which may be attached to the lining already) to the upper collar only. Match notches and marks and sew along the upper collar only.
3. Sew the front edges. Pin and sew the facing’s front edges to the jacket from hem to lapel corner. Trim the seam allowances to 1/4 inch.
4. Trim and understitch the front edges. Clip at the lapel roll line, the point at which the lapel folds back and the facing turns to the outside. Bevel or grade the seam allowances, switching sides at the clip to keep the wider allowance facing out. Understitch the seam allowances (see “Understitching Secrets” below for tips on this step). Switch the side you understitch at the lapel roll line, so that the understitching is on the inside.
5. Sew the corners. Sew across the lapel’s top edge from the corner to the end of the collar. Stitch over the collar/neckline seam about 3/4 inch on each end. Clip through all the layers to the seamline exactly where you stopped stitching.
6. Clip the collars’ seam allowances frequently, then press open. Open the collar/facing and collar/jacket seam allowances. A seam board or point presser can help with this step.
7. Finish the lapel. Join the lower seam allowances of the jacket and facing necklines across the back. Leave about 1 1/2 inches free at each end to the clip from step 5. Trim the corners and turn the lapels. Follow pattern instructions to complete the jacket.
Understitching is pressing the seam allowances of an edge seam toward the piece that will be underneath (such as the facing, the undercollar, or the back of the lapel) and stitching them down, usually 1⁄8 inch or less from the original seam.
The technique automatically “rolls” a seam slightly out of sight toward the garment wrong side as you form an edge.
When there’s a corner, as on collars and lapels, understitching helps keep it precise. Flat and folded seam allowances are key for sharp corners. An understitched seam is folded, fixed, and ready to turn cleanly.