When to Use a Straight or Zigzag Stitch
Deciding whether to use a straight stitch or a zigzag stitch in your sewing project can be a gray area. What are the qualities of straight and zigzag stitches? Is there a certain advantage to using one over the other? These are all questions every sewer has had during a project. Let’s discuss the major differences between straight and zigzag stitches, their benefits, and when to use each stitch type.
For the purposes of this blog, we will only be comparing straight and zigzag stitches in reference to lockstitch sewing machines. Lockstitch sewing machines are the only type of machine we sell, and they're also the most common type of sewing machine our customers use. In a lockstitch sewing machine, a lockstitch is created when the upper thread and the bobbin thread lock together as they pass through the hole created by the needle. The knot created by the interlocked stitches is hidden between the layers of your fabric assembly, and the stitches on the top and bottom of the fabric look identical.
Benefits & Uses for the Straight Stitch
The straight stitch is the most basic sewing machine stitch. It’s also known as a construction stitch because it is used to fabricate sewn shaped items and is the stitch you will use most often. The straight stitch is used in the three most popular canvas seams: the overlapping seam, the semi-flat felled seam and the full-flat felled seam. A straight stitch creates a perfect fold line, which makes it ideal for flat felled seams in which the fabric assembly is splayed open when sewing the topstitch seam.
Qualities of the Straight Stitch:
- stretch resistant
- efficient — uses less thread than zigzag
- less visible than zigzag
- the only stitch you’ll need for most sewing applications
If you know that all you will ever need is a straight stitch, it’s advisable to invest in a well-made straight stitch only sewing machine. Machines that only sew a straight stitch are generally more robust than similar machines with multiple stitch patterns. If you’re unsure whether you need a zigzag stitch for the types of projects you sew, refer to the last section for a chart we made listing the preferred stitch type for the most common sewing projects and techniques.
Benefits & Uses for the Zigzag Stitch
Often called an accordion stitch, a zigzag stitch has both a stitch length and a stitch width. These measurements do not need to be the same. For example, you can have a zigzag stitch with a 3mm length and a 6mm width. When bar tacking, you want a shorter stitch length and a wider stitch width. On most zigzag stitch sewing machines, you can set the zigzag width anywhere from 0mm to the machine’s highest width setting. A zigzag stitch with a 0mm width is a straight stitch.
You might be thinking you’d never use a zigzag stitch, but you’d be surprised at the usefulness of this specialty stitch. Did you know you can use a zigzag stitch to enclose or serge raw fabric edges to reduce fraying? This technique comes in super handy if you don’t own a serger machine or a hotknife to seal raw fabric edges. Even if you do own a hotknife, you can only use a hotknife on synthetic fabrics which melt, thus sealing the edges and preventing fraying. To enclose the raw fabric edges, sew a row of zigzag stitches slightly over the raw edge of the fabric into the adjacent material.
Qualities of the Zigzag Stitch:
- creates stretchy seam that will elongate
- distributes stress well across seams — essential in sailmaking
- the broad stitch width holds down wide seam areas well
- more decorative than straight stitches
- easy to remove with a seam ripper
One of the most common uses for the zigzag stitch is to sew stretchy materials. When sewing a material that stretches, such as knitted fabrics and neoprene, it’s essential to use a stitch that can stretch with the fabric. If you use a straight stitch when sewing stretchy material, the stitches will create puckering and possibly break when the material is stressed.
Although sailcloth has evolved over the years, and what was once a somewhat stretchy material is now dimensionally stable, sewing sails with the zigzag stitch is still the traditional, preferred method. Zigzag stitches distribute the strain over multiple runs of warp threads, which creates a seam with stretch that allows for movement of sail shape without seam puckering. Additionally, spinnaker sails are sewn with nylon, which is a stretchy material. The use of the zigzag stitch in spinnaker sail construction is imperative.
Stitch Type by Project
Now that you know the basic differences between a straight stitch and a zigzag stitch, as well as the benefits and qualities of each stitch type, let’s take a look at common sewing projects and the stitch type we recommend. The chart below lists some common marine, outdoor and upholstery sewing projects including canvaswork, awnings, clothing and leatherwork, sailmaking, window treatments and more. Use this list to determine whether to use a straight or zigzag stitch for your project.
We hope this blog has cleared up any confusion about straight and zigzag stitches and when to use them in your sewing projects. If you have any further questions, don’t hesitate to call, email or online chat with us. We’re happy to help with all your sewing needs. Do you have any additional uses for straight or zigzag stitches than the ones listed above? Leave your thoughts in the comments section below!