Insert your needle into the machine with the flat side backward. Push the needle up as far as it will go and tighten the screw. Machine embroidery is fast and a loose needle will cause problems.
TYPES OF NEEDLE Machine embroidery needles are designed for machine embroidery so should always be used, unless a specialty needle is required (see below). A machine embroidery needle has a longer, deeper scarf where the thread sits than a machine sewing needle. This is to allow for the high speed of the threads running through the needle. The eye is also larger and rounder, so the thread causes less friction when passing through.
NEEDLE SIZES Needle selection is based on fabric. You need to use the correct size because the amount of needle penetration in and around a design causes holes in the fabric, which are unsightly if they are too big. The needles range from size 60 for extremely fine fabric through to size 110 for upholstery fabrics. Pictured: Embroidery needle size 90: This needle was chosen in order to penetrate the dense denim fabric. Denim can support higher stitch counts without needing a heavy stabilizer. An iron-on fusible tearaway was used to hold the stretch in the denim still.
SPECIALTY NEEDLES Occasionally, an embroidery design calls for a specialty needle. These needles are a little more expensive than ordinary needles but, as they are seldom used, they do last a long time.
TWIN NEEDLES These are needles with two points, with a determined space between the points ranging from 1⁄16 to 3⁄16in (2 to 5mm). These needles require two threads, one threaded normally, the other either on a bobbin or another spool of thread on your top spool pin (this can be built-in or an accessory) and threaded alongside the first but through the eye of the second needle. An embroidery design that uses a twin needle will be digitized to allow for the specified size of twin needle. Always use the needle size stated in the design, otherwise you will hit the needle plate and break it. The design’s documentation will tell you when to use the twin needle. Pictured: Twin needle: The embroidery is stitched on cotton fabric with a lightweight cutaway stabilizer, and so a size 80 embroidery needle was used. A size 80 twin needle with a 3⁄32in (2.5mm) gap was used in the twin needle areas.
TOPSTITCH NEEDLES These are used if the thread is thicker than normal—for example, decorative or wool-based threads. The point is larger, but so is the needle eye. They are available in different sizes but a size 90 is suitable for most machine embroidery requirements. Use the topstitch needle for the part of the design that uses the thicker thread and swap back to an embroidery needle afterward.
METALLIC NEEDLES These are used with metallic threads: the thread will break and snap if you don’t use one. The groove is deep for the thread to sit in and the eye is large and more oblong than round. Metallic needles range in size and you select the size according to your fabric. Sizes 75, 80, and 90 should be sufficient for most applications. Pictured: Metallic needle: This design is stitched on cotton with a medium-weight cutaway stabilizer and a size 80 embroidery needle. The metallic areas were stitched with a size 80 metallic needle.
BALLPOINT NEEDLES These are not generally used in machine embroidery, but can be useful when stitching on stretch or T-shirt fabric. The point is rounded, so it slips between the fibers rather than splitting them. Unfortunately, they don’t have the design of machine embroidery needles so you are likely to experience thread shredding and breaking. Whether or not you use these really depends on the quality of the T-shirt or stretch fabric. Pictured: Ballpoint needle: Stretch T-shirt fabric is used here. A size 70 ballpoint needle was used to stop the fibers in the fabric from splitting. To hold the stretch on the fabric still, fusible polymesh stabilizer was used.
NEEDLE BREAKAGES Needles break a lot and this is probably not because you are doing something wrong. A needle breaks when the machine wants to stop suddenly. It is the machine’s way of saying that it wants to stop sewing. Have a look to see what the problem is before continuing. Most likely is that your top thread has twisted and jammed, the bobbin thread has caught up, or the part of the embroidery you are sewing is too thick. Rectify the problem, switch to a new needle, and continue sewing. If the embroidery is too dense for the size you are using, go up a size and try again.
NEEDLE LIFE SPAN Needles do not last long. The life span of a new needle is roughly 10,000 stitches before it begins to blunt. A blunt needle will cause problems: threads will break, pull the embroidery out into loops, catch on stitches, and generally spoil your work. Change needles often. A blunt needle is the cause of most embroidery problems.
This article is excerpted with permission from <a href="http://amzn.to/1vgxE28">"The Sewing Machine Embroiderer's Bible: Get the Most from Your Machine with Embroidery Designs and Inbuilt Decorative Stitches"</a> by Liz Keegan (St. Martin's).