Sewing a cylinder means joining two rectangular pieces of fabric into a tube, then closing one or both ends
A cylinder is the foundation for dozens of projects: pillowcases, bags, sleeves, pouches, and lampshades all start as a sewn tube. The basic method is straightforward—fold your fabric, sew a seam down the length, and finish the raw edges. If you need a closed cylinder (like a pillow), you'll then sew the ends shut. The hardest part is usually keeping your seam straight and handling the fabric smoothly as it curves around the presser foot.
This guide walks you through the two main approaches: sewing a flat rectangle into a tube, and sewing two separate pieces together. Both use the same principles, and once you've done one, the other takes minutes.
Key Takeaways
- A cylinder starts as a rectangle sewn lengthwise into a tube, with the seam running parallel to the length of your finished project.
- Press your seam open or to one side before closing the ends, so the finished cylinder lies flat and looks professional.
- Use a 1/2-inch seam allowance unless your pattern specifies otherwise, and backstitch at the start and end of every seam to lock the thread.
- If your cylinder will be turned right-side-out (like a pillowcase), leave a 3- to 4-inch opening unsewn so you can flip it and stuff it.
- Test your seam on scrap fabric first if you're new to sewing tubes—it takes only a minute and catches mistakes before they're in your real project.
Measure and cut your fabric to the right dimensions
Measure the circumference of the finished cylinder you want. If you're making a pillow that's 12 inches around, cut your fabric 13 inches wide (12 inches plus 1 inch for two 1/2-inch seam allowances). The length of your rectangle becomes the height of your cylinder—if you want a 16-inch-tall pillow, cut the fabric 16 inches long.
Mark these measurements lightly on the back of your fabric with a pencil or fabric pen. Use a ruler or measuring tape, not your eye. Even a quarter-inch error compounds when you're sewing a seam that wraps around, so take the extra 30 seconds to measure twice.
If your pattern calls for two separate pieces instead of one folded rectangle, cut both pieces to the same width and length. They will be sewn together along their long edges to form the tube.
Fold and pin the fabric before sewing
Lay your rectangle on the table with the right side (the side you want to show) facing up. Fold it in half lengthwise so the two short ends meet and the right sides face each other. The fold runs along one long edge. Pin along the open long edge, placing pins every 2 to 3 inches perpendicular to the edge you're about to sew.
If you're using two separate pieces, lay them right sides together and pin along one long edge. The pins should go straight across the seam line, not parallel to it—this lets you remove them as you sew without snagging the presser foot.
Check that the edges line up evenly. Misaligned edges now mean a lopsided cylinder later. Run your finger along the pinned edge to feel for bumps or shifts.
Sew the seam with a straight stitch
Set your sewing machine to a straight stitch with a stitch length of 2.5 millimeters (a standard setting on most machines). Thread the machine and test the tension on a scrap of the same fabric folded the same way—a balanced stitch looks the same on both sides, with no loops or puckering.
Position the fabric under the presser foot so the needle will enter 1/2 inch from the raw edge. Lower the presser foot and backstitch three or four stitches to lock the thread. Then sew forward along the length of the fabric, removing pins as you approach them. Keep the raw edge aligned with the 1/2-inch mark on the needle plate (most machines have a line marked there). Sew all the way to the end, then backstitch again to lock the thread.
The seam should be straight and even, with stitches the same length throughout. If you see puckering or skipped stitches, stop, raise the presser foot, and rethread the machine—usually the issue is thread not seated in the tension discs. Do not try to sew over a problem seam; remove it with a seam ripper and start again.
Press the seam open or to one side
Remove the fabric from the machine and trim any loose thread ends with scissors. Lay the tube flat on an ironing board with the seam running down the center. Set your iron to the heat appropriate for your fabric (check the fiber content on the bolt or pattern)—cotton and linen take high heat, synthetics and blends take medium.
Press the seam flat first, then open it so the two layers of fabric lie flat on either side of the seam line. This is called pressing the seam open. It reduces bulk and makes the finished cylinder look neater. If your pattern specifies pressing the seam to one side instead, do that—some projects need the seam allowance folded toward one layer for strength or appearance.
Let the fabric cool before moving it. Hot fabric is stretchy and can distort if you handle it too soon.
Close the ends of the cylinder if needed
If you're making a closed object like a pillow or a pouch, you now have a tube with two open ends. Fold the raw edges of one end inward by 1/2 inch and press them flat. Fold them in again by another 1/2 inch and press. This is called a double-fold hem. Pin the fold closed.
Sew the fold shut with a straight stitch, stitching as close to the inner fold as you can—usually about 1/8 inch from the edge. Backstitch at the start and end. Repeat on the other end, or leave one end open if your project calls for it (like a pillowcase that will be stuffed).
If you're making something that will be turned right-side-out before closing (like a pillowcase), sew both ends shut now, but leave a 3- to 4-inch opening in one seam. After you turn the cylinder right-side-out through that opening, you'll hand-sew it closed with a ladder stitch or whip stitch.
Turn the cylinder right-side-out if you left an opening
Reach into the opening you left and grab the far end of the tube from the inside. Pull gently and steadily until the entire cylinder turns inside-out, bringing the right side of the fabric to the outside. This takes a little patience—go slowly so you don't tear the seams. Use a chopstick or point turner to push out the corners or edges if your cylinder has them.
Press the finished cylinder flat again, paying special attention to the seams. The opening you left should now be on the inside (if you're making a pillow) or on the outside (if you're making a bag you'll stuff). Stuff the cylinder if needed, then hand-sew the opening closed using a ladder stitch: bring the needle out through the fold of one side, cross to the opposite side, go in through the fold, travel inside the fold for 1/4 inch, come back out, and repeat. The stitches will be nearly invisible.
Common mistakes and how to avoid them
Uneven seams. The most common error is letting the fabric shift as you sew, so one side ends up wider than the other. Prevent this by pinning every 2 inches, not just at the ends, and by keeping the raw edge aligned with the needle-plate marking the whole way. If it happens, use a seam ripper to remove the seam and sew it again.
Puckered fabric. Puckering usually means the thread tension is too tight or the needle is bent. Test the tension on a scrap first. If the scrap looks fine but your project puckers, the needle may be damaged—replace it and try again. Never sew over a puckered seam; it won't improve with pressing.
Forgetting to backstitch. If you don't backstitch at the start and end of a seam, the thread will unravel the moment you pull on the fabric. It takes two seconds and prevents hours of frustration. Make it a habit.
Seam allowance too wide or too narrow. A seam allowance that's off by 1/4 inch changes the circumference of your cylinder by 1/2 inch, which is enough to make a pillow or sleeve not fit. Measure the seam allowance on your first inch of sewing and adjust the needle position if needed before you continue.
Frequently Asked Questions
Can I sew a cylinder on a serger instead of a regular sewing machine?
Yes. A serger creates a stronger, neater seam and finishes the raw edges at the same time. Use a 4-thread serger stitch and follow the same pinning and pressing steps. The main difference is that a serger takes up more seam allowance (usually 5/8 inch instead of 1/2 inch), so measure your fabric width accordingly.
What if my fabric is stretchy or slippery?
Use a ballpoint or stretch needle instead of a universal needle—it slides between fibers rather than piercing them, which prevents runs and skipped stitches. Pin more frequently (every 1 to 2 inches) and sew slowly. Consider using tissue paper or stabilizer under the fabric as you sew; tear it away afterward.
How do I sew a cylinder with a pattern or stripes that need to match?
Lay the fabric out flat and check where the pattern will meet when you fold or join the pieces. Mark the fold line or seam line with a pencil on the back of the fabric so the pattern aligns. Pin carefully along this line before sewing. Take your time—matching patterns adds time but makes the finished project look handmade in the best way.
Do I have to press the seam, or can I skip that step?
Pressing is not optional if you want a professional result. It sets the stitches, removes wrinkles, and lets you see whether the seam is straight. A cylinder that hasn't been pressed will look rumpled and unfinished even if the sewing is perfect. It takes five minutes and makes a huge difference.
What stitch length should I use for a cylinder?
A standard stitch length is 2.5 millimeters, which works for most fabrics and projects. Use a slightly shorter stitch (2 millimeters) for delicate or lightweight fabrics, and a slightly longer stitch (3 millimeters) for heavy fabrics like canvas or denim. Avoid very short stitches (under 1.5 millimeters) unless your pattern specifies them—they can weaken the fabric by perforating it too much.