Tips & Tricks | Stitching and Cutting Corners Correctly

One of the common areas of sewing frustration, especially if you're new, is the corner. Those pesky four corners create any square or rectangular item, like the home décor standard: the pillow! In reality, any time you sew two pieces together then turn them right side out, that turned-out seam becomes the clean, finished edge you (and everyone else) will see. The number one goal when sewing a corner is to be precise. You must stop and pivot at the exact point where the seam allowances on the two sides intersect. This precision stitching, when combined with proper trimming of the excess fabric from the seam allowance, will create a beautiful sharp point and smooth edge every time.

Sounds simple, right? Mostly it is, but there are some techniques about stitching and clipping corners that will help you maintain the best, cleanest shape every time. From curtain panels to pillow edges to accessory details, by following a few simple steps, you'll never be backed into a corner again!

Everyone's favorite corner is the right or 90˚ angle. You'll find them on pillows, panels, placemats... as well as other items that don't necessarily start with a "P"! These corners come in TWO types: inward and outward. The two are sewn in a similar fashion, but clipped differently.

Although most corners in home décor projects are of the right angle variety, others can be more like a point (or acute angle, which means less than 90°). We used these in our Gypsy Romance 3-D Triangle Pillows.

Then there are the obtuse angles, which means more than 180°. We encountered these on the flap of our Scrap It: Gift Card Case/Biz Card Holder.

And you thought you'd never use geometry when you got older!

When you venture into garment sewing, you're likely to see a lot of stitching and clipping of corners on collars and cuffs. The good news is, you'll be ahead of the learning curve thanks to this tutorial.

In our examples below, we used a bold red thread so you could see and understand the technique. In actual application, you would select a thread to coordinate with your fabric. In the majority of our photos, we also used our Janome Open Toe Satin Stitch foot so you could clearly see all the stitching. For the majority of corner stitching, a standard pressure foot is the best choice.

Sewing and trimming an OUTWARD right angle corner

1. When starting out, regardless of the angle, it's a good idea to mark the seam allowance a couple inches from the corner along both sides on the wrong side of your fabric. This will enable you to clearly see where the lines intersect and improve your stitching accuracy. For right angles, it's fairly easy to determine where the two seam allowances intersect by measuring from each corner.
2. Using your seam allowance measurement (our standard home décor allowance is ½"), measure in from each corner edge with a ruler or seam gauge. About 3-4" should be enough.
3. With a fabric marking pen or pencil, mark the pivot point on each corner.
   
4. With your fabric right sides together, begin to sew along the seam allowance. As you approach the corner (and your drawn lines), get ready to stop and pivot at the marked point.
   
5. Stop with the needle in the down position. Lift up your presser foot, pivot, lower the foot back into position, and continue sewing.
   
   NOTE: Remember, in many cases, you will need to leave an opening somewhere in the seam in order to turn your item right side out.
6. With a pair of small, sharp scissors, trim the seam allowance at the point.
7. First, trim off the corner point at a diagonal, being very careful not to clip your stitches.
   
   NOTE: If you do accidentally clip into your seam, don't just leave it. There will be a hole at the corner and the weakened seam could continue to open up. Take the time to turn the piece inside out again and re-stitch the seam! This means you will not have much, if any, seam allowance to work with, so you'll need to sew carefully. Stay as close to where you clipped as possible without comprising the shape of your overall project.
8. After you trim off the point, trim along each side at an angle from the point. This will ensure a sharp corner.
   
9. Turn the piece right side out to see how your point looks. Not so good? That's because you need to gently push out the corner with a point tool. There are a number of different ones you can use, we've pictured an "official" point turner in our photo, but you can also use a simple chopstick or a long, blunt-end knitting needle.
   
10. If you were a little shy about your clipping, you'll feel the extra fabric bunched up in the corner; it kind of feels like a little knot. That means you need to go back in and trim a little more.
11. Press your project from the right side and admire your sharp little corner.

Sewing an INWARD right angle corner

1. Mark your corner points in the same manner as above.
   
2. Sew as before, pivoting at the marked corner point intersection.
   
3. This time, instead of cutting off the point, you need to clip into the point. Again, be careful to not cut through your seam.
   
4. Turn your project right side out and see how the corner looks. As above, if needed, turn it inside out again and trim away more seam allowance at the corner.
5. You'll notice you can see one of our red stitches from the right side. You will be stitching with matching thread, so no worries if a thread peeks thtrough.
   

A stitch length option

1. Sometimes, depending on the fabric type or weight, you may need to adjust your stitch length at each corner. In fact, some sewing experts recommend doing this at any corner in your sewing.
2. When approaching your corner, shorten your stitch length a distance equal to your seam allowance. Do this both coming into and going out of the corner. In our sample, this meant we shortened the stitch length ½" before and after the corner pivot point.
3. This helps insure a sharp point and helps strengthen the corner.
   

Added layers

1. When you have an added layer in a corner, like batting, everything is sewn in the same manner as we've been discussing.
   
2. When you're done stitching, first trim the excess batting to approximately ⅛" from the stitching line. This reduces the bulk. Next, go back and clip the corner fabric layers as described above.
3. It's often a good idea to trim back the batting around the entire project, rather than just at the corners, especially if you plan to use a line of topstitching along the seamed edge on the right side.
   

Different weight fabrics

1. To fully educate you on all we know about corners, we have to mention an option for dealing with various weights of fabrics. As above with the batting, the idea is to eliminate excess bulk in the corner that prevents you from effectively turning out each point. Believe it or not, sometimes the best way to create a point is to not sew one to begin with!
2. Mark your seam allowance as shown above, but instead of pivoting at the intersection of the two seam allowances, sew ACROSS the pivot point. The general rule is on lightweight fabrics (see our example below), sew one stitch across, on medium weight fabrics sew two stitches across, and on heavier weight fabrics sew three stitches.
3. You would think you'd lose the point, but you'll actually get a good looking one.
   

Acute and obtuse points

1. Acute and obtuse angled points are sewn the exact same way as the right angles; they just look a little different.
2. Mark your seam allowance and intersecting or pivot point. On the left is our marked acute angle; on the right is a marked obtuse angle.
   
3. Sew as normal, stopping to pivot at your marked point. You're starting to get the hang of this now!
   NOTE: When you are sewing acute angles, we recommend considering the "cross stitch" method described above. Because the acute point is so narrow, sewing across the pivot point with a stitch or two can be quite helpful. In addition, extra care and a slower speed is recommended because the raw edge can be stretchy (the exception to this would be if you are working with an interfaced piece like the point of a collar). 
   
4. Trim the point and seam allowances. The acute angle trims in the same manner as an outward right angle.
   
5. The obtuse angle should be trimmed as more of a simple slope from the point down either side.
   
6. Obtuse angles turn right side out the easiest of all the angles, which makes sense because there's more room at the point.
7. Acute angle points sometimes need a little more coaxing. You can use a point turning tool as we recommended above, but you may find the very tip of the point still doesn't want to turn. To fix that, all you need is a trusty straight pin. Insert the straight pin into the tip of seam from the right side and gently pull/pick out the point into shape.