Sewing Machine Help..! Help And Advice On How To Repair Sewing Machine Problems

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Overlockers and Caring for your Serger Overlockers and Caring for your Serger - FAQ

  1. Explain to me about the types of overlock stitches

    A 5-thread stitch is ideal for sewing and finishing woven fabrics. It is the industry standard. It consists of a straight seam (chain stitch seam) and a 3-thread overcast stitch. A 3 or 4-thread overcast can be used on most woven fabrics, but several types of fabrics tear away from these stitches, especially if the seam is under strain or the fabric is loosely woven. The 5-thread double chain stitch is a stronger seam than the 3- or 4-thread overcast. Because the 5-thread overlock combines a chain stitch with a finishing stitch over the edge, it is also a safety stitch.

    A 4-thread overlock is used for sewing seams and many other specialty techniques. The 4-thread seam is very secure for most sewing and has a safety stitch running down the middle of the overcast.

    A 3-thread overlock can be done both as a wide and narrow stitch. The 3-thread overlock is used for seams on knits, or when there will not be a lot of stress on a seam. It is also used for decorative techniques, blind hemming and narrow and rolled edges.


    The primary advantage of a 2-thread stitch is to provide a lighter finish or stitch. Several stitches can be done with a 2-thread setting including a 2-thread fladock, 2-thread rolled edge, and a 2-thread overlock. The 2-thread overlock or seam finish can be used to finish an edge before you sew with a straight stitch.

    The rolled edge can be done with two or three threads. A 2-thread rolled edge uses less thread and results in a softer, finer finish for lightweight and sheer fabrics. A rolled edge can be used as a seam in very lightweight fabrics where the seam allowance may show through to the right side. The rolled edge can be used to finish tablecloths, napkins, or home decor projects. It can also be used as a hem for lightweight garments or scarves. Decorative edges can be achieved by placing decorative thread through the loopers. Sewing over a strand of yarn with decorative threads creates a beautiful braid that can be used to embellish crafts or garments.

    The flatlock can be sewn with two or three threads. It can be a decorative stitch. Specialty thread in the upper looper is used to show the flatlock side of this stitch. Decorative thread in the needle is used to show the ladder side of the stitch

    3 mm AND 6 mm COVERSTITCH:
    A cover stitch is used for a truly professional hem on knits, lingerie, and activewear. It is also used as a decorative topstitch. The greatest advantage of the cover stitch is its elasticity on knits and other stretchy fabrics.

    The triple cover stitch uses all three front needles and the chain stitch looper to provide the greatest elasticity of all the overlock stitches. This stitch is also used as a decorative hem or topstitch.

    The chain stitch is not stretchy, but has more give than a standard straight stitch making it an excellent alternative seam stitch for fabric that tends to pucker. The speed of the overlock machine and this stitch are very beneficial for the many long straight seams in home decor sewing. A 2-thread chain stitch will stabilize seams in loosely woven fabrics and knits. It can also be used to fit a garment. Release the chain stitch to remove the stitching quickly, decorative threads may be put in the chain stitch looper for a decorative chain stitch. Silk buttonhole twist, rayon, and fine metallic threads work well for this. Quilting fabric from the wrong side with a decorative chain stitch nicely and provides a pretty accent.

  2. Overlock needles and special thread

    Overlock Threads
    Unfortunately, when overlockers first came on to the market, it was often thought that any old cheap thread would do. However, this is untrue. Threads that are too strong may bend the loopers of the machine and fine cheap threads may break easily so the inexpensive cones which are sometimes sold as overlocker threads may not be a bargain after all! Buy threads with a gauge of 120 or check the manual of the machine to make sure they are the correct type a good quality thread with an even twist and no loose fibres will be best for a machine and give a perfect stitch.

    Using Decorative threads
    Decorative threads or fine ribbons can be used in the upper looper. Check that they will not be too thick or strong first as they may damage the loopers. Turn the machine by hand first then stitch slowly.

    Needle Type
    General sewing machine needles are not always the correct ones to use in an overlocker; indeed damage may be caused by using the incorrect type of needle. Check the manual for details, as it will recommend the best ones for the make and model of the overlocker. As with conventional sewing, the choice of needle also depends on the type and weight of the fabric, for example, fine needles for thin/lightweight fabrics or stretch needles for knitted/jersey fabrics. Also, change needles frequently and ensure both needles are the same type and size when doing four-thread overlocking.

  3. Yes I know, but what is a cover stitch?

    Cover stitch or sometimes called a cover hem?
    A cover stitch appears on many shop bought clothes. It is a professional hemstitch that overlocks the raw edge on the wrong side and at the same time produces a neat even top stitch, usually, (two or three rows) on the right side. Many overlockers now offer this feature, using a different number of threads. Probably the most popular is the 2-needle, 5rnm wide cover stitch usually found on shop bought garments.

  4. General tips and helpful hints

    Never drop another needle into machine
    When removing needles from an overlocker leave them threaded up or put a piece of cloth underneath. If the needles are dropped in the process, then they can be easily retrieved and so will not drop into the mechanism and cause damage.

    It needs tender loving care
    Keep overlockers and covered when not in use. This prevents them from getting dusty and discolored by sunlight.

    Dont stitch over pins
    this will damage your knife blades. Learn to "finger pin" as you overlock. Use as few pins as possible. Try to use pins with large heads in a contrasting color to the fabric. Place them at a 90-degree angle several inches from the edge of the fabric, and they will be out of the way as you stitch by them.

    Before you start
    Check the position of the blade. Make sure the blade is either fully engaged in position to cut or is disengaged. Turn the blade or knob until it fully clicks into or out of place.

    Safety first
    Always have the looper cover closed whilst overlocking. We don't want you or the fabric to get caught in the moving parts. Some models will not operate if the foot pedal is pushed when the looper cover doors are open.

    Never pull the fabric
    Don't push or pull the fabric as you serge. Let the feed dogs pull the fabric through the overlocker. All you need to do is guide the fabric and let the overlocker do the work. You can bend the needles by pulling the fabric.

  5. Tell me more about overlockers...?

    What is an overlocker, why use one, what can it do?
    If you need to sew stretchy seams, use fabrics that fray, or just want speedy sewing, you will love an overlocker (or Serger as it is known in the USA). Think of today's leisure wear, popular fleece, children's clothing, body-clinging evening dresses, swimwear, or even stretchy knitted tops. They can all be sewn on an overlocker? and fast.

    What is Overlocking?
    It is the ability to complete three sewing tasks at the same time - and quickly. Overlocking sews the seam edges to join layers, trims the edges of the fabric neatly, and over-sews the trimmed edge to prevent fraying - all at once. The main advantages are, of course, the speed at which one seam is completed and how easily it is completed, providing a stretchy stitch that is perfect for jerseys, knits, t-shirt fabric etc. Overlocking is also ideal for fabrics that fray easily as one-step stitching/neatening means less handling and less opportunity for the fabric to fray, as well as providing a lovely neat finish.

  6. Why use a overlocker and not a sewing machine

    Sewing machine or overlocker ?
    You can achieve similar seam finishes on your sewing machine, by using an overlock stitch or close zig zag stitch however, an overlocker does it quicker, neater and of course in one-step. Today overlockers can also be used for many other types of sewing, not just to complete straight seams. For instance, the cutters can be switched off so that you can do applique, you can gather, hem in a variety of ways (depending on the foot used), make pin tucks, create decorative braid and add elastic easily.

  7. Overlocking Terminology

    A few of the words that you will hear are as follows:
    Serger - this is an American term for Overlocker. Serging is therefore overlocking.

    Loopers - instead of bobbins, an overlocker has loopers. The threads that come from under the needle plate are the lower looper threads and those from the top are the upper looper threads. Each looper has its own tension adjustment dial.

    Cutter / Knife - an overlocker has a knife or knives to cut the fabric edge before it is overlocked. These can usually be turned off so that seams can be sewn uncut - useful for patchworking, invisible hemming etc. Some of the latest models have a swing-away cutting knife which makes threading and cleaning easier.

    Cops/cones - thread for overlockers usually comes on a tall, conical shaped cone that holds 1000 meters. Overlocking uses much more thread than conventional sewing, however, overlocking thread is usually much less expensive!.

  8. Help with threading an Overlocker

    Threading needles
    Loosen the tensions down to zero when threading. This allows the thread to properly seat itself between the tension disks. Reset the tensions after threading is completed. You have to turn those dials! Some modern overlockers have a tension release and do not need to be reset manually.

    If you tie on to rethread "don't sew the knots through your machine!" Set the tension to zero, work the chain loose behind the foot and pull one or all the threads through by hand. Use the tweezers and grab the thread behind the eye to pull one thread through at a time. Unthread the needle eyes before pulling the thread through so you don't bend the needles!

    How to thread loopers
    If the lower looper thread breaks, "always un-thread the needles before threading the lower looper" If you don't, the needle thread will be trapped between the lower looper and the lower looper thread. You will have to rethread because the lower looper thread will break again when you take a stitch. When the needle threads are first threaded, the thread goes through the eye and straight back. When the first stitch is made, the needle thread goes under the needle plate, wraps around the lower looper from front to back and then goes into the thread chain. If you thread the lower looper from scratch and leave the needle threads wrapped around the lower looper, the needle threads will be trapped and cause the lower looper thread to break repeatedly until you remove the needle threads from being trapped between the lower looper and the lower looper thread.

    Always thread an overlocker in the correct order. This may vary from brand to brand so check the manual for the recommended threading order. This is an important step to follow and helps reduce the chance of trapping the threads. Make sure to get comfortable with the threading order of your overlocker.

  9. What is differential feed

    An overlocker without a differential feed is as much use as a sewing machine without a needle..!

    Differential feed on an overlocker has two feeds, the front feed and rear feed. They can move the fabric under the presser foot by different amounts. e.g one feed moves further or faster than the other.

    For example a regular overlock machine without differential feed has one single feed dog to move the material under the foot.

    A Singer overlocker with differential feed, uses two feed dogs, both work in unison to feed the fabric by the exact same amount or they can be set to feed material by different amounts.

    If both feed dogs are adjusted to feed fabric at different amounts, this adjustment is by a simple dial usually on the side of the overlocker, it adjusts the differential feed ratio.

    The differential feed ratio is the difference in movement between both feed dogs.

    Adjusting one way will stretch the fabric, whilst adjusting the other way will contract the fabric, especially noticeable on lightweight or stretch materials.

    Knitted fabrics tend to stretch when sewn, so setting the differential feed to a high number will help stop this stretching.

    Whilst woven fabrics can contract, you would set the differential feed to a lower number will help give a perfectly flat seam.

    Differential feed means that the layers of fabric are fed through evenly which helps prevent knitted fabrics from puckering and woven or sheer fabrics from wavering. 

    Using a special accessory foot you can gather or ruffle fabric, or create a lettuce leaf effect while overlocking, thanks to the differential feed.

  10. Keep it clean

    Too much lint
    Lint from the cut fabric builds up in the machine and if not removed, will cause problems and can soak up the oil (which lubricates the machine) and get caught under the stitches and moving parts. Use a small brush to remove the lint; do this between each garment made. Some fabrics are more prone to causing lint buildup than others - when working with fibrous fabrics such as fleece and woolens, brush away the lint more regularly.

    Do Blades need replacing often
    The time the blades will last in the machine is dependant on how often the machine is used and the materials that are run through it. They do however need to be replaced if the edge face becomes shiny, as they will blunt. Certain fabrics such as velour or surface texture fabrics, can seriously damage the blades so check them after using this type of fabric.

    Cleaning Tensions
    Tie several knots in a length of buttonhole thread then dip it in white spirit. Pull this back and forth through the tension dials to get rid of lint build-up.

    How often an overlocker needs to be oiled will depend on how the machine is used and where it is stored. The general recommendation is that an overlocker is oiled after every eight hours of actual running time but if a machine has been left unused for some time it should be oiled. Also, oil more frequently if the machine is stored near a radiator. Always use specific sewing machine oil, not general household oil as it is too heavy. Follow the manufacturer's instructions when oiling an overlocker - the manual will recommend oiling points where there are moving parts. When oiling, turn the mechanism by hand then leave it overnight for the oil to settle before using the machine

    How often an overlocker needs servicing will depend on how much it is used. As a general guide, however, plan on a service every two to three years.

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