how to thread a serger

Threading a serger

Threading a serger can be a daunting task for some new users. Follow the threading diagrams in your owners manual and read the instructions below for added insight about threading. If you run into trouble do not get upset. If the machine is not threaded correctly it will not make stitches correctly and probably will break the thread. If after you try several times, you still can’t get the machine to run correctly, check to see if there is a video available that shows the threading of your exact model of machine. Instructional videos are often made available on the Internet and on YouTube. Sometimes seeing a video can make things easy to understand that otherwise seem complicated.

Know that after you successfully thread the machine a few times it will become easier, you just have to get through the initial learning curve. If you can’t master it, get help from someone with experience. After you do it a few times successfully it will be no problem for you. If you are having trouble it is probably some small thing you are missing. Sergers must be threaded exactly or they wont run correctly.

Remove all thread from the serger before threading. If it is a new machine then it probably came properly threaded from the factory so you may want to study the threading before removing the existing thread.

There is no universal threading procedure for sergers, every model has a different thread path so it is important follow the threading diagram in the owners manual for your specific model. Some machines have the threading diagram printed on the machine (usually on the inside of the looper cover). Most machines have color coded marks or dots along the thread path, if you have experience with sergers you may be able to properly thread the machine using the color codes if you do not have an owners manual or threading diagram.

Chain-off after threading:

After the machine is threaded, hold the threads toward the back of the machine (pulling lightly) and turn the hand wheel in the correct direction a few times (counterclockwise for most machines) to intertwine the threads. Watch to make sure a chain is being formed correctly before running the machine under power to make about 4 inches of chain. This is known as chaining off. Once your machine is chained off like in the picture below you are ready to start serging.

Threading Tips:

  • Double check your threading, many serger problems are due to improper threading.
  • Use the tweezers! Most sergers come with tweezers but if yours did not come with them, get some. Tweezers allow you to thread the loopers, in most cases your fingers will not fit in the required space or will block you from seeing what you are doing.
  • It helps to have a brightly lit area, use a reading lamp or other directable lamp to shine more light in the thread path area for better visibility while threading.
  • Threading by “tie-on” is not recommended. Tying-on is done by tying the new thread to the old thread and then pulling the old thread through the serger until the knot is pulled through and then cutting the knot off. By the time you tie the knots for each thread this will end up taking more time than threading the machine normally. If you learn to thread the machine normally it will get faster every time you do it and you will not need to tie-on.
  • Reading glasses can be used as a handy magnifier for threading the machine and inspecting stitch quality (even if you don’t need them for reading). Reading glasses are much better than a magnifying glass because they allow the use of both hands and give you much better depth perception than a magnifying glass because each eye has its own lens. The best magnifications for this type of use are +1, +1.5, +1.75 or +2 depending on your eyes. Reading glasses are very inexpensive so you might try a +1.5 to start and then get a second pair that is stronger or weaker later.
  • Make sure that each thread is inserted all the way between the tension disks or into the tension slot. Pull each thread after threading the tension disks to make sure that you feel consistent thread tension. If you don’t feel proper thread tension then perhaps the thread is not going through the disks properly or the disks are fouled with lint or old pieces of thread.

Setting the thread tension

  • All sergers have recommended tension settings that are given in the owners manual for that specific model of machine. Some sergers have a mark or special color on the tension dials that indicate a default or starting tension. A default tension will produce a usable stitch in a medium weight fabric when using regular serger thread and a medium stitch width and medium stitch length. If your owners manual gives you specific tension recommendations for different thicknesses and types of fabrics then use the recommended tension settings for those fabrics.
  • Test the machine on a scrap of the fabric. If the stitch looks good then your tension settings are adjusted properly and you are ready to sew!
  • Some owners manuals do not specify a fabric weight or type. In this case you should use the recommended (or default) tensions and first test the machine with two layers of medium weight fabric (such as cotton or polyester bed sheet or pillow case fabric). If the stitch looks OK then try the fabric you are going to be using and see how the stitch looks. If the stitch looks good then your tension settings are adjusted properly and you are ready to sew!

Serger operation

Before starting:

  • Make sure that the machine is properly threaded and chained off and that the tension controls are properly set.
  • Always keep your fingers away from the needle and looper area while the machine is running.
  • Set the stitch width – Set it to a medium setting like 5mm unless you have a reason to use a different setting.
  • Set the stitch length – Set it to a medium setting like 3mm unless you have a reason to use a different setting.

Starting your seam:

  • Raise the presser foot and insert the fabric under the front of the presser foot so that it is just touching the blade of the cutter. Lower the presser foot.
  • Start the machine slowly and make sure that the fabric is feeding correctly into the cutter. If you are sewing fleece or other thick fabric you may have to re-position it and try again to get the fabric to start feeding through the machine. Make sure that fabric is not bunched up against the cutter blades and feeds correctly through the cutter when you start the machine. Do not push the fabric, let the machine feed the fabric.
  • Lightly place your fingers on the fabric to the left of the presser foot to guide the fabric through the machine.
  • Once the machine is running and you see the stitch is forming correctly then increase the speed of the machine.
  • For thick fabric – When sewing thick fabric and using the cutter pay special attention the entire time you are running the machine to make sure that the cutter is cutting the fabric cleanly and that the fabric is not jamming up in the cutter. Unless you have a heavy duty serger with a heavy duty cutter sometimes it is better to cut thick fabric before running it through the serger and then use an edge guide instead of using the cutter. Some machines have a cutter lock screw to better secure the cutter when cutting thick fabric. Check your owners manual to see if your machine has a locking cutter.
  • Do not push or pull the fabric through the machine. Let the feed dogs of the machine move the fabric. Only use enough effort to guide the fabric in the direction you want to sew. The feed dogs are timed to only move the fabric when the needle is in the up position. If you try to push or pull the fabric through the machine you will move the fabric when the needle is down and you will bend the needle possibly causing the needle to hit the needle plate and break. This can damage the machine.

Ending your seam:

  1. Let the fabric go completely through the machine and then run the machine a bit more to produce about five inches of chain. After the fabric ends lightly pull the fabric to the rear of the machine while the chain is being made. Once the machine stops you can cut the chain and remove the fabric, leave about three inches of chain on the machine.
  2. If you want to end the seam before the end of the fabric you can serge off the side of the fabric and then run the machine a bit more to produce about five inches of chain. This does not look very good but if the seam will be on the inside of the item you are sewing the looks are not important.
  3. Alternatively if you want to end the seam before the end of the fabric you will need to get the thread to release from the stitch finger of the machine as follows; Stop the machine in the place you want to release the fabric. Rotate the hand wheel to bring the needle to the up position. Grab the needle thread above the needle and pull about one inch of needle thread from the tension disks. Now raise the presser foot and move the fabric to the rear of the machine so that the stitches can slide off the stitch finger. Once the fabric is free from the stitch finger you can move the fabric to the left so that the fabric is not under the presser foot. Now run the machine to produce a few inches of chain and then cut the chain.

Now you have completed a seam, but the beginning and end of your seam has a few inches of chain hanging from it. If you cut the chain off, the stitch will unravel.

Tips, tricks and pointers

Starting a seam – Some people prefer to start a seam with the presser foot down. This is done by lifting the front of the presser foot with your finger and placing the fabric under the front without raising the foot. Alternatively some people just start the machine with the foot down and then insert the fabric under the front of the foot until the feed dogs grab the fabric. These methods are not recommended because they cause the machine to run with the pressure foot in direct contact with the feed dogs (no fabric) and will eventually wear out the feed dogs and presser foot

Do not sew over pins – you will damage your machine. If you do pin your fabric make sure the pins are well away from the edge of the fabric or remove the pins as you sew and before they get to the cutter blades and needle area of the machine.

You can start fast! – You don’t have to always start slowly, if you are sewing long seams and need to go fast then mash on it! Sergers are designed for full power start-and-stop sewing.

Thin fabric – To sew very thin fabric that does not feed well or bunches up you can add a layer of thin paper or stabilizer material under the fabric. After sewing tear off the part of the paper that is visible.

Feed dogs – Don’t push or pull the fabric, let the feed dogs move the fabric through the machine. Your job is to guide the fabric so that the stitching is in the correct place.

Stretchy fabric – To sew stretchy fabric like knits or spandex set the differential feed to a stretch setting.

Chained off – At the factory when the machine is new it is said to be “chained off” when it is tested with a small piece of test fabric after being set up and adjusted. This piece of fabric is usually left in the machine under the presser foot as proof that the machine was working correctly when it left the factory or repair facility.

Test sew – Use a piece of scrap fabric to test sew and inspect the stitches before sewing something important. For test sewing it is best to use opposite colors of thread and fabric so that the stitches are clearly visible. How does the stitch look? Is the tension correct and is the stitch balanced?

To go slow – Most sergers don’t go slowly very well. If you need to go slower than your machine likes to go under its own power then you should use manual power (rotating the hand wheel of the machine with hand power). Do this whenever you need the machine to sew very slowly with a great deal of control.

Skill – Its mostly skill that gets good results, not the machine! The machine is just a tool, you control what the machine does.