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01.08 Sew a Busted Seam

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A busted seam is a classic technique often found in jeans, which leaves the seam allowance flat and open, creating a clean and durable finish. This method prevents the seam edges from unraveling while maintaining the fabric’s structure.

Sewing the Seam

  1. Place the edge of your fabric along the serger’s blade. You’ll want to trim just a tiny amount, barely a hair’s width. This step ensures that the edges are clean and won’t fray while keeping as much seam allowance as possible.
  2. When you finish serging the edge, pull the fabric away from the machine, creating a chain of thread that hangs off both the fabric and the machine. This chain helps prevent the serger stitches from coming undone.
  3. Place the two pieces of fabric with the right sides together, aligning the freshly serged edges.
  4. Set your regular sewing machine to a straight stitch. Align the fabric under the presser foot, aiming for a 5/8-inch seam allowance.
  5. Start sewing, running a few stitches forward. Backstitch to secure the beginning of the seam. When you reach the end of the seam, backstitch again to lock the stitches.
  6. Then, raise the needle, lift the presser foot, and gently remove the fabric from the machine. Trim any excess threads for a clean finish.

Pressing the Seam Open

  1. Lay the fabric flat with the right side facing down. Gently open up the seam so that the serged edges are on either side of the seam line.
  2. Using a hot iron, press the seam allowance open. This action is what “busting” the seam refers to. By pressing it flat, you ensure that the seam lays nicely against the fabric and that the finished piece will look smooth and professional.
  3. On the outside, the fabric should appear as a straight seam, and on the inside, you’ll see the neatly serged and separated seam allowances pressed open.

How to Sew a Busted Seam Video Transcript

In this sewing tutorial we’re going to learn about a busted seam. This is a very common seam in jeans and to get started we’ll take our fabric and sew right along the edge barely trimming off a hair’s width with our serger to keep the ends of the fabric from fraying. As you can see here i’m just barely taking off a bit of the fabric and then the fabric end is all encapsulated with the overlock serging stitch and it will not unravel. Make sure when you trim you have some of that chain hanging off the machine and your fabric so the stitching doesn’t come undone.

Then i’ll go ahead and do this for the other side ,once again lining up the edge of the fabric just along the blade of the serger that way we don’t take off too much of the seam allowance to change the dimensions of our pattern and the fit of what we are sewing. Once you finish the seam pull it through, make a long chain leave some length on both the machine and the fabric to keep things from unraveling.

Now we’re ready to go to our regular sewing machine and make our busted seam. At the regular sewing machine we’ll place this right sides of the fabric together lining up the serged edges of the fabric. These should be very straight because they were just trimmed. Then we’ll go ahead and sew a standard 5/8 inch seam allowance. Line up our needle, we’ll stitch a bit and then we will backstitch, then sew straight along 5/8 of an inch all the way down to the bottom. And then we will stop at the end and back stitch to secure the stitching. Raise your needle then remove the fabric and trim all excess threads.

When we unfold the fabric you can see it looks like a standard straight seam on one side but now we have these pre-serged edges that are separate and then we can go to the ironing board and we can press these open. Here I am pressing it open with the iron. This is the busting of the seam, busting it open and once that’s done it’ll look nice and straight on one side and flat just like a pair of pants. And then on the inside, if you take a look at many of your ready to wear jeans you’ll see this exact finish.

And then we go ahead and hem the bottom if we want, we’ll press this with the iron as well after we folded this up twice and this will take care of those extra serger threads at the bottom that way they won’t unravel because they’re encapsulated inside this folded hem. So press it down with the iron, this will make sewing it much easier because everything will stay in place. Take your time and make everything be straight.

Once it’s pressed down then we can take it back to our sewing machine and go ahead and stitch this hem down. There are many ways to hem or finish the edge of fabric this is just a simple fold it over twice way and then stitching along the edge. When we go past the busted seam this is encapsulating everything and nothing will unravel and you have a fully finished piece of fabric and a seam that lays very flat on the inside.

Here we are a busted seam and now you can sew one yourself. Happy sewing everyone.