Pressing vs. Ironing in Sewing and Quilting
@Missouri Star
@Professor Pincushion
@Fons & Porter’s Love of Quilting
Step-by-Step Instructions:
There is a golden rule in sewing and quilting: we press our seams, we do not iron them. Understanding the difference between these two motions is the secret to ensuring your blocks stay perfectly square and your garments drape beautifully without stretching out of shape.
Materials Needed:
- Iron (with or without steam)
- Ironing board or wool pressing mat
- Tailor’s clapper (optional but helpful)
- Spray starch (optional)
Tips for Success:
- Let the heat and weight of the iron do the work for you. Do not push or force the iron across the fabric.
- Allow the fabric to cool completely before moving it to set the seam permanently.
1. Understand Ironing
- Ironing involves sliding the iron back and forth across the fabric, applying downward pressure. This is great for getting wrinkles out of a finished dress shirt, but sliding the iron over freshly sewn seams will stretch the fabric (especially on the bias) and distort your piece.
2. Understand Pressing
- Pressing is an up-and-down motion. You lift the iron completely off the fabric, move it to the next spot, and press it straight down. This applies heat and weight to flatten the seam without dragging or stretching the fibers.
3. Set the Seam
- Before opening your fabric, lay the piece flat on your ironing board exactly as it came out from under the sewing machine. Press the iron straight down onto the stitches for a few seconds. This “sets the seam,” sinking the thread into the fabric fibers to make it stronger and flatter.
4. Finger Press First
- Open your fabric pieces. Use your fingers to gently push the seam allowance to one side (or press it open, depending on the pattern). Finger pressing ensures you don’t accidentally iron a fold or pleat into the front of the fabric.
5. Press the Seam Flat
- Gently place the iron straight down over the opened seam. Hold it there for 3 to 5 seconds. Lift the iron completely up, move it to the next section of the seam, and place it straight down again. Repeat until the entire seam is flat.
6. Let it Cool (or use a Clapper)
- Fabric retains heat, meaning the fibers are still malleable when hot. If you pick up the piece immediately, it might lose its shape. Leave it flat on the board until it is cool to the touch. For extremely flat, professional seams, place a wooden Tailor’s Clapper over the hot seam immediately after lifting the iron; the wood absorbs the heat and steam, locking the seam perfectly flat.
Top FAQs for Pressing vs. Ironing:
What is the difference between pressing and ironing? +
Ironing is a sliding, back-and-forth motion used to remove wrinkles from finished clothing. Pressing is a strict up-and-down lifting motion used in sewing to flatten seams without stretching or warping the fabric pieces.
Why shouldn’t I iron my quilt blocks? +
Quilt blocks are full of seams, many of which are cut on the bias (the stretchiest part of the fabric). If you slide a heavy iron across them, the fabric will warp and bow. Your blocks will no longer be perfectly square, making them nearly impossible to piece together accurately.
What does “setting the seam” mean? +
Setting the seam happens right after you sew it. Before opening the fabric, you place the hot iron directly onto the closed seam. This relaxes the thread and sinks the stitches deep into the fabric fibers, making the seam much flatter when you finally open it.
Should I use steam when pressing? +
It depends on the fabric. Steam is fantastic for flattening stubborn seams on cotton. However, steam can also cause delicate fabrics to distort, shrink, or water-spot. If you are sewing lots of bias edges (like triangles), a dry iron is safer to prevent stretching.
What is a tailor’s clapper? +
A tailor’s clapper is a smooth block of hardwood used heavily in garment making and quilting. Immediately after pressing a seam with hot steam, you press the clapper firmly over the seam. The wood absorbs the heat and moisture, instantly “locking” the seam completely flat.
Should I press seams open or to the side? +
In garment sewing, seams are almost always pressed open to reduce bulk. In quilting, seams are traditionally pressed to one side (the darker side, so seam allowances don’t show through) to make it easier to “nest” intersecting seams together.
