These hems are often seen on the edges of napkins or table linens, the edges of ruffles, scarves and much, much more. The type of fabric being sewn basically determines whether you use the narrow hem or the rolled hem.
As this is National Serger Month, we’d like to share with you some tips for achieving the best results possible when sewing narrow hems and rolled hems on your SINGER serger. We’ll start by explaining basic machine set up (regardless of which type of hem you want to sew). Then we’ll explain the differences between the narrow hem and the rolled hem, how to do small stitch length adjustments to fine-tune the look of the stitches just the way you want them, and a few troubleshooting tips as well.
No matter which hem (narrow or rolled) you want to sew, the stitch finger must first be adjusted accordingly. Doing this means that the width of the finger (on which the stitches are formed) becomes smaller so that machine can sew narrower stitches. For most current machine models, this is done simply be moving a lever at the front of the machine (forward position for narrow and rolled hemming). Some older models required changing of either the stitch plate or the changing the stitch finger itself, so check your machine manual.
The stitch length is usually shortened so the stitches sew closer together and less fabric is visible between the individual stitches. The smaller the stitch length setting number, the closer together the stitches will be to one another. The larger the stitch length setting number, the farther apart the stitches will be. Some models may have a setting designated by an “F” which means “fine”, indicating that model’s shortest stitch length setting. Changing the stitch length will change the look of the hem, depending on the fabric you are sewing. Experiment on scraps before sewing your project.
Only the right needle is used. The left needle is not just unthreaded – it must be completely removed from the machine or the stitches will not form properly.
Leave the cutting blades engaged. Fabric is sewn with the fabric right side up, and as you sew, the excess fabric is trimmed, providing a cleaner finish than if you try to stitch without trimming.
Adjust the position of the lower cutting blade, setting it so that the fabric is trimmed more narrowly than it is for regular serger stitching. With less fabric in the hem, you’ll have a cleaner, finer finish. For most current models, the lower blade adjustment is done by turning a dial near the front of the machine. For details on how to adjust the position of the lower cutting blade for your particular serger model, consult your instruction manual.
When sewing a narrow hem, the threads ‘meet’ at the very outside edge of the fabric. The fabric edge remains flat and is not rolled over to the back side as the stitches are formed. The narrow hem is a good choice for medium-heavy weight fabrics, as these fabrics generally resist “rolling”. This hem is typically slightly wider than the rolled hem due to the fact that the fabric isn’t being rolled, but it is narrower than using a regular 3-thread stitch as an edge finish.
A narrow hem is sewn with 3 threads – the upper looper, the lower looper, and the right needle. You can use serger thread in both of the loopers and the needle. Generally, the thread tensions will be set very similarly to the way they are for regular 3-thread overlock stitching.
When sewing a rolled hem, the fabric edge “rolls” over as the stitches are formed. The stitches that appear on the top side of the hem are also visible on the bottom side of the hem. The rolled hem is a good choice for lightweight, medium weight and sheer fabrics like cotton, organza, organdy, silk and chiffon.
A rolled hem is sewn with 3 threads – the upper looper, lower looper and right needle. You can use serger thread in both of the loopers and the needle. However, the thread tensions are adjusted to create the “rolling” effect at the edge of the fabric. The upper looper is loosened, allowing more thread into the stitch so that it can appear on both the top side of the fabric and the bottom side. The lower looper tension is tightened so that there is less of the lower looper thread on the underside, since the upper looper thread will wrap around to the back.
Whether you are sewing a narrow hem or a rolled hem, sometimes small adjustments to the stitch length will allow you to fine-tune the look of the stitch just the way you want for your particular project. Always test-sew on a scrap fabric so you can adjust the stitch as desired for the particular fabric you are sewing.
You can sew hems with a longer stitch length setting, which means that there is more space between the individual stitches. This will allow the hem edge to be more ‘fluid’, especially with softer fabrics.
You can sew hems with a shorter stitch length setting, which means that there is less space between the individual stitches, but this will usually require some adjustment to the tension settings. When the stitch length gets shorter, there is usually too much thread for the space allowed with each stitch, so it will be necessary to adjust the tension to compensate for this.
(See photo: Left shows shorter stitch length, right shows longer stitch length)
If sewing a narrow hem on a project where you want the fabric edge covered completely (no fabric showing between stitches), but the stitch length setting is set the way you want it for your project, you may want to consider using a texturized nylon thread in both the upper and lower looper. This thread is thicker and provides more coverage than regular serger thread. When using this thicker thread, you can leave the stitch length setting a bit longer than when sewing with regular serger thread.
If the hem is tearing away from the edge of the fabric, it could be that the stitch length is set too short for the fabric being sewn, causing perforation. Try increasing the stitch length, which should eliminate the perforation effect.
Check your manual for the correct style of needle to be used with your serger model. For sewing medium weight fabrics, use a size 14 serger needle. For lightweight or sheer fabrics, use a size 11 serger needle, which is finer. Using a needle too large for the fabric may result in holes at the stitching line.
If the fabric seems a bit “puckered” along the stitching line, you could try decreasing the differential feed setting slightly. This will cause the front part of the feed teeth to move a bit more slowly relative to the back part of the feed teeth, which works to help remove puckers as you sew.
Depending on fabric type and weight, you may see thread bits – sometimes referred to as “pokies” – showing at the fabric edge and sticking out between the stitches. You could try spraying the fabric with fabric spray starch, which will put a little more body and stability in the fabric as you sew.
Sew a thread chain before placing the fabric into the machine. Hold the thread chain lightly as you begin to sew. When you finish sewing the fabric edge, or when you sew off to form a corner, apply a drop of fabric seam sealant. Let it dry completely before trimming away the remaining thread chain – if you trim the thread chain before it is dry, the stitches may begin to come undone.
Enjoy sewing with your SINGER serger!