How to Use a Rotary Cutter to Cut Fabrics

Rotary Cutting Safety Tips
Emilia Kun / E+ / Getty Images
Overview
  • Total Time: 4 hrs
  • Skill Level: Beginner

Rotary cutting long strips of fabric is the starting point for most rotary cutting tasks used in today's quilt patterns, especially strip-pieced quilting projectsIndividual patchwork shapes can be sub-cut from strips as needed. Accurate rotary cutting is essential for successful quilts and quilt blocks. New quilters can save money by practicing with inexpensive muslin or bargain fabrics before cutting more expensive quilting fabrics.

The instructions for most quick-pieced quilt patterns tell you to rotary cut long strips of fabric from selvage to selvage, across the fabric's crosswise grain, and that's what we'll cover in this tutorial. However, it's fine to work with shorter strips until you are comfortable with long ones, and strips of fabric cut along the fabric's less stretchy lengthwise grain work nicely, too.

Notes

Read through all the instructions to get an overview of the process. If you are still new to working with fabric, you may want to make sure you understand some basic terms and techniques

  • Always check the state of your tools: is the blade of the rotary cutter sharp? Dull blades cut poorly, and are more of a safety concern than sharp ones.
  • Always roll the rotary cutter away from your body and follow any safety guidelines that came with your cutter.
  • Never use a rotary cutter on any surface other than a rotary mat.
  • Crisp fabrics are easier to rotary cut. Use spray starch or sizing to make fabrics stiffer.
  • Attach gripping tabs to the bottom of rotary rulers to help keep them from slipping on fabric. Many types of grippers are available commercially, including clear versions that won't obstruct your view of ruler lines.

The instructions are written for working right-handed. If you are left-handed, work from the opposite side of the fabric, placing fabric and rulers in mirror-image positions.

What You'll Need

Equipment / Tools

  • Rotary cutter
  • Rotary cutting mat
  • 1 long quilting ruler
  • 1 square quilting ruler

Materials

  • Fabric to be cut

Instructions

  1. Square Up the Fabric

    Before you rotary cut the long strips required for a quilt pattern, it's important to square up one end of the fabric. After squaring up, the leading edge should be at a 90-degree angle to the fold.

    1. Fold the fabric along its length, selvages together. The bolt fold should be straight, with no pull lines. If it isn't, press out the bold fold and refold it with selvages matched and parallel.
    2. If you are working on a small rotary cutting mat, you may need to fold the fabric lengthwise again, making it four layers deep. If at all possible, beginning quilters should stick to one fold; each new fold makes inaccurate cuts more likely.
    3. Place the fabric on the cutting mat, fold near the bottom edge, side to be squared on the left. Line up the fold with one of the horizontal lines on the cutting mat, or, if your mat is unlined, use a square rotary ruler. The square ruler's left edge should be near, but inside the left edge of the fabric, roughly where you will make your square cut.
    4. Place a long rotary ruler to the left of the first ruler on top of the leading edge of the fabric and flush against the square ruler. Make sure a horizontal line on each ruler is precisely matched to or parallel to the fold.
    5. Remove the square ruler. Place your hand firmly in the vertical center of the long ruler to hold it in place and roll a rotary cutter from bottom to top along the ruler's right edge. Spread your fingers out to hold the ruler securely, but take care to keep fingers out of the cutter's path. A commercial tool such as the RuleSteady can help keep fabrics from shifting and protect your hand.
    6. The fabric's cut edge should now be at a 90-degree angle to the folded edge.

    The end of your fabric is now squared up.

    Tip

    Some quilters square up an edge from the right side of folded fabric, aligning a rule on the ruler with the bottom edge and trimming off a small excess on the right. Afterward, they flip the fabric around and cut from the left. We prefer the method explained in the steps above since there's no need to flip the fabric around, which sometimes allows its layers to shift.

    Diagram to fold fabric for rotary cutting
    Janet Wickell
  2. Cutting Long Strips

    With the edge squared up, it's time to rotary cut the fabric strips required for your project.

    • Align the mark on the long ruler that corresponds to your desired strip width to the left edge of the fabric. Check it lines up along the entire length of the ruler. Make sure a horizontal line near the bottom of the ruler lines up with the fold. For example, use the 3 inch mark on the ruler to make a 3 inch wide strip.
    • Cut along the right side of the ruler with the rotary cutter.

    It's not unusual for the leading edge of the fabric to become out of square after several cuts. Square up as many times as necessary to keep strips accurate. Before you make each cut check to be sure that the left and bottom edges of the fabric align with vertical and horizontal markings on the ruler. If they do not, square up the end again before cutting more strips.

    Tip

    To make sure the leading edge of the fabric is at a 90-degree angle to the bottom of the strip, open one of your rotary-cut strips to its full width and look at the area near the fold. If the piece has a bend in the middle, the fabric's left edge is no longer square. Correct the problem, and move on.

    Diagram re checking strips for accuracy
    Janet Wickell
  3. Cutting Segments from Strips

    Place your rotary ruler near the right end of a cut strip, aligning a horizontal rule with its lower edge. Cut along the right edge of the ruler to square up the end of the strip.

    Turn the strip around and cut segments from its left edge in the same way you cut the original fabric strips, aligning the strip with markings on the ruler as required for each shape.

  4. Cutting Bias Strips

    Long (stretchy) bias strips are sometimes used to make quilt binding and for applique shapes that bend easily into graceful curves, such as flower stems.

    • Align the 45-degree mark on a long rotary ruler with the fold in the fabric's bottom. Hold the ruler in place and cut along its right edge.
    • Align the correct line on your ruler with the angled edge of the fabric and the 45-degree line with the fold. Rotary cut along the right side of the ruler again. 

    Continue until you have the number of bias strips required for your quilting project.