Threading the Needle

I am a self-professing thread snob.  I admit it and own the title. 

However, I didn’t realize how passionate I was concerning the subject until I had a discussion with a few quilters a while back.  The topic was  thread, what kind we used and why.  I was amazed at the variety of preferences across the Zoom meeting.  I was even a bit taken back at myself and why I thought my favorites were the best.  There were several quilters who disagreed with me and were just as passionate about their choices.  All of this back and forth got me thinking about thread and why I use what I use and where I use it.

I do think some thread brands are better than others, and since I’m not monetized by any of them, I will spill the beans about what brands I love and use regularly.  I don’t use cheap thread in my Janome M7 Continental.  She doesn’t like it.  However, my long arm loves cheap thread.  Go figure.  I also use only long-staple threads because short-staple threads as a whole are linty.

Before we jump into all of this, I’d like to take the time to briefly talk about the types of thread available, their construction and why it matters, weight, and a rule of thumb about sewing machine needles and thread.  In this blog, we’re only discussing thread based on sewing machine use.

Types of Thread

  1. Cotton – Cotton threads are made from twisting the fine staples (fibers) from a cotton boll to create a thread.  There are many degrees of cotton-quality.  There are extra long staple cotton fibers made from Egyptian or Pima fibers, there are long cotton staples made from Sea Island cotton, and short staple cotton which primarily comes from the United States.  Each of these types of cotton fibers play a very important part in our textile world, but the long and extra-long staple make the best thread (in my humble opinion).  Cotton thread is known for its strength, medium sheen, and the natural fibers help grab the fabric to create a tight seam.  However, it’s difficult to tell low-quality from high-quality cotton thread and some manufacturers have gotten sneaky (and unethical – again, my opinion) and mix the staples and call their product long-staple thread.  Quality cotton thread is one of those quilting items that “you get what you pay for.”  In other words, higher quality cotton thread will cost you more pennies.  Cotton thread has a low-to-high lint residue depending on how it was processed, the staple length, and the quality of cotton used. 
  2. Core-spun Polyester (also called poly-wrapped core) – We quilters of a certain age remember the polyester hey days of the Seventies in all their glory.  As a result, we tend to disdain anything remotely related to the term.  However, today’s polyester thread isn’t like your mother’s.  It’s so, so, much better.  Core-spun polyester threads have a filament polyester core that is wrapped with spun polyester.  The advantages of core-spun polyester threads are its strength, reduced puckering, and excellent stitchability. It does produces low to moderate lint.
  3. Filament Polyester – Filament polyester threads are made from long, thin strands of polyester fibers which are twisted together.  The advantages of filament polyester are excellent elongation (the fibers and stretch and recover), smooth presence with no lint and can be finished as a thick or thin thread.  However, these threads are not as strong as core-spun and finer filament threads may require some tension adjustments on your sewing machine.

4. Monofilament Polyester – Monofilament polyester threads are single threads of polyester fiber, similar to fishing line.  This is a very fine thread that blends well and can be ironed with medium heat.  Usually tension adjustments will need to be made on your machine.  I use this thread to stabilize my quilt sandwich prior to quilting, since the stabilization usually means I’m using the stitch-in-the-ditch method around the center square(s).  This thread does tend to curl a bit. Some sewing machines are bothered by this, and others aren’t.  If your machine pitches a temper-tantrum with Monofilament, you may want to set the spool in some kind of holder (a coffee mug works great) and then position it a few feet from your machine.  This extra thread-path allows the thread to “relax” a bit before reaching your machine. 

5. Spun Polyester – Spun polyester threads are made from twisting small polyester staple fibers together to create a long thread (similar to the way cotton threads are created from cotton staples).  The primary advantage of Spun Polyester is price.  It costs less to make, so it costs you less.  The disadvantages are lint and strength.  This thread produces moderate to high levels of lint and it’s not as strong as filament or core-spun polyester.

6. Rayon – This is thread created in a chemistry lab.  Cellulose acetate (generally made from wood pulp) is pressed through small holes and solidifies in the form of filaments.  This thread has a high sheen, it’s soft to the touch, and it’s relatively inexpensive.  However, it’s not color fast.  Strong detergent, UV light, or bleach can cause it to bleed onto fabric.  It’s also not as strong as trilobal polyester and not as durable as polyester.

Rayon Thread

7. Nylon – This thread can run the gamut from monofilament to textured and fuzzy.  The disadvantages of this thread far outweigh any positives.  This thread should be avoided in both quilting and other types of sewing, as there are so many other better choices.  Bonded nylon is available, and it’s better than regular nylon, but it’s a heavy-duty thread used in upholstery and other heavy duty sewing.

8. Metallic – Metallic threads are created from multiple layers of materials wrapped and twisted together.  This is one thread you really need to be sure is manufactured well, because quality can range from high to extremely poor.  A good metallic thread does not require a lubricant and has a strong nylon core, a thin layer of rice paper, and a special outer coating which keeps the foil from rubbing against the needle.  The sheen is beautiful, and it has excellent stitch quality when it’s used in embroidery, quilting, or sewing.  Tension adjustments may need to be made and sewing speed slowed down.   

Mylar Thread

9. Glitter or Mylar – Mylar threads are created by bonding thin layers of flat mylar material.  Glitter thread offers holographic effects and can be used with embroidery, quilting, or regular sewing.  The disadvantages of Glitter or Mylar thread are the same ones most specialty thread has – you may need to adjust the tension and slow down your stitching speed. 

Processing Methods

Sewing and quilting thread (so we’re talking about cottons and polyesters, not specialty threads such as monofilament or glitter) undergo processing such as twisting, lubricating, and winding. In addition, cotton threads can have the following additional treatments:

Mercerized – Mercerization is the process of immersing the cotton fibers in a caustic solution which causes the fibers to swell.  This allows the dye to better penetrate the fibers and increases the luster of the thread.  Mercerizing also increases the strength of the cotton thread.  Nearly all cotton threads made for sewing are mercerized whether the label states it or not.

Gassed – Gassed thread has been passed through a flame at high speed to burn off the longest pieces of lint, resulting in a less fuzzy thread.  Gassing is also called silk finished or polished cotton as the thread has lower lint and brighter sheen than other thread.  You can tell the difference between gassed and ungassed thread if you compare the amount of fuzz between two threads.  The lower the fuzz, the better the chances the thread has been gassed. 

Glazed or Coated – Glazed thread is treated with a coat of wax, resin, or starch and then polished to create a luster.  The thread is very strong due to the glaze and is recommended for hand quilting.  Glazed cotton threads are not recommended for machine sewing or machine quilting because the coating can rub off in the tension discs and contact points.  Then the discs and points will collect lint, fuzz, dust and cause a buildup to obstruct the thread path.

It’s All About the Weight

For me the most important characteristic about the thread I use to piece and quilt my quilts is the weight.  The weight or size of the thread is an important consideration for any sewing project.  Knowing how to make proper adjustments relative to different thread weights will make sewing, quilting, or embroidery projects more enjoyable.  However, just to make things a little more interesting (and sometimes confusing), there are five common methods used to measure thread:  Weight, denier, tex, number, and composition standards.  I won’t go into all the equations and such used to come up with these.  Instead I want to give you the down and dirty, so you won’t have all these numbers swimming around in your head. 

Weight – The smaller the weight number the heavier and thicker the thread.  A 30-weight thread is heavier than a 40-weight thread.  A 40-weight thread is heavier than a 50-weight one, and so on.  Most thread purchased in the United States mentions the weight on the spool label, the spool rim, or the inside of the spool. 

Denier – This measurement deals primarily with polyester and rayon embroidery thread.  Most polyester and rayon threads are 120/2 meaning two strands of 120-denier thread for a 240 denier total.  All this boils down to the fact the larger the denier number, the heaver the thread.

Tex – This is the weight in grams of 1000 meters of thread.  If this total weight is 25 grams, it’s a 25 Tex.  Bottom line – the larger the Tex number the heavier the thread.

Number System or Gunze Count System– Here’s where the whole thread measurement process can get a bit confusing.  The Number standard is used on many thinner threads and is written as No. 50 or #50 or No 100 or #100.  Many folks confuse this with the Weight measurement and incorrectly suppose the weight and number is the same thing – such as a #100 thread is the same thing as a 100-weight thread.  Like the Weight measurement, the smaller the number the heavier the thread. 

It can boggle the mind when you’re shopping for thread, because one thread which is stamped #50, another 50 wt, and another 50/3 are not the same.  All three are measured by different standards and may not be similar in size.  What is important is to keep a consistent standard of measurement when purchasing certain threads and use your eyes and fingers to gauge the diameter of the thread.

Where Composition Standard Comes into Play

This standard was originally developed for cotton thread but is now also used for polyester.  A cotton thread and a polyester one with identical composition numbers will be similar, but not exactly the same size.  This is technically because we’re comparing apples to turnips.  For exactness, compare cotton thread to cotton thread and polyester to polyester.  And for us the Composition Standard deals with interpreting a chain of numbers.  For instance, some spools may be stamped with something like 30/3 (or 30/1×3).  The first number – in this case 30 – is the same number used in the Number Standard.  So this thread is a No. 30 thread.  The second number – 3 – means the thread has 3 plys twisted together to make one thread.  We now know we have a No. 30 thread comprised of 3 plys, which means this is a heavy thread and a thick thread since it’s made of three plys.  Rule of thumb if you see a composition standard listed on a spool of thread:  Most thin threads (50 wt. and thinner) are a 2-ply thread.  Most heavy threads are a 3-ply thread.  I realize this may seem like we’re really into the minute details about thread, but this information is helpful when determining needle size.

So Why Is All This Information Important?

The weight is important because it concerns stitch density, needle size, and tension.  If you’re a quilter who uses their embroidery machine for quilting or to add designs to blocks, generally you use 40-weight thread.  This ensures adequate coverage.  If a heavier thread, such as a 30-weight, is used, a lumpy appearance may result or cause the thread to bind on itself, which means it will continuously break or jam the machine. 

However, let’s consider weight with regard to the seams in quilt blocks.  One thing quilters need to do is consider the entire quilt before putting in the first cut of the fabric.  And in all honesty, if you’re a new quilter, this is difficult.  I also think it’s harder to do if you don’t quilt any of your own quilts either on a long arm or domestic machine.  In one way quilting is like just about any other craft or art — what you do now affects the other steps you take later.  One of those steps which need careful consideration at every point is bulk.  You want to keep the bulk to a minimum with every step of construction.  Here’s where the weight of the thread comes into play with seams:  Use a high weight thread both on the top of your machine and in the bobbin.  My go-to piecing thread is 50- or 60- weight Aurifil. 

I love Aurifil for piecing.  It has 2-plies and is a strong thread.  It takes up little space in the seam itself, making your ¼-inch seams extremely accurate.  It’s long-staple, low lint, and comes in hundreds of colors.  I have two on-line sources for it:  Red Rock Threads and Pineapple Fabric.  While I can find Aurifil in quilt stores, I have yet to see it in a big box store such as Joann’s.

If I can’t find what I need in Aurifil, my second piecing thread choice is Superior Thread’s Bottom Line.  Designed for bobbin use, Bottom Line is a 60-weight, 2 ply, polyester thread, but it’s a great piecing thread.    And right here I will pause because I can hear the arguments starting:

“You can’t use polyester thread on cotton fabrics!  The polyester thread will cut right through the cotton.”

Nope.  Won’t happen.  Remember when I told you that today’s polyester threads are nothing like the kind used by our mothers?  Those old polyester threads may have very well sawed their way through the few available garment cottons because those cotton fabrics meant for clothing are thinner than quilting cottons.  However both today’s fabric quality and polyester thread quality are  much better and this doesn’t happen.  But there is something to be careful about – thread shrinks when it’s washed, and cotton and polyester thread have different shrink rates.

And this is the point where I will get serious about dropping name brands because I’m not monetized:  I’ve never had the shrinkage issue with Bottom Line.  It’s an awesome thread.  If you were to visit my quilt studio, you’re likely to find just as many spools and cones of Bottom Line as you do Aurifil.  I use Bottom Line not just for piecing, but also for invisible applique and binding.   

The new kid on the block (at least in the United States) is Wonderfil.  I had the amazing experience to use a sample of this thread about three years ago and it was love at first stitch.  Unfortunately, it wasn’t available in the United States then, so I was pestering my Australian and Canadian connections for a few spools here and there. Thankfully, it’s now available in the US (I didn’t know this until I visited a quilt shop in Florida while I was in Palm Coast to see my son – I did a happy dance in the aisle and I’m sure they thought I was bonkers).  Wonderfil produces a thread called Invisafil which is 100 weight, cottonized polyester. 

This thread is truly the best of both worlds.  Because it is cottonized, there is negligible stretch and because it’s also polyester, it’s strong and feels soft.  Used as piecing thread, it practically disappears in the seams and it’s great for micro stippling or any other quilting stitch you would prefer to have disappear into the background of your quilt.  It’s also perfect for invisible applique or hand applique.  Bonus for those of us who like prewound bobbins – Invisafil is available in those.  Wonderfil thread is available at

Of course, the best thread in the world is nothing without the correct needle.  I wrote a blog about sewing machine needles and what sizes are best for different fabrics and thread.  It’s a lot of information.  However, there is a handy, dandy rule of thumb about thread and needle sizes:  Generally, use a needle whose eye is 40% larger than the diameter of the thread.  So, a #75/11 or #80/12 needle is great for 50-weight thread.  One of the wonderful things about Superior Thread is they tell you what size long arm or domestic machine needle is needed on the inside of their spools and cones. 


If you’re sewing away and find your thread is shredding and breaking or you are the victim of skipped stitches, stop sewing.  The first line of defense in this situation is to change your needle.  If it continues to happen, go up one needle size.  I tend to be a big Schmetz needle fan.  I’ve used them since I began sewing 38 years ago and they’ve always served me well.  However, be aware some sewing machines are brand-specific as far as their needles go – such as Singer.  Singer machines work best with Singer needles.

The last issue to talk about concerning thread is tension, and this is one of the issues which causes quilters’ hackles to rise.  We want to thread the machine, insert fabric, and get with the sewing.  However, no matter how much we dislike dealing with tension, it’s one of those things that can make a great sewing day (the tension is perfect) or it can cause us to want to throw our machines out the window (the tension is awful).  If you use the same brand and weight of thread all the time, tension isn’t an issue.  However, if you’re like a lot of quilters and you change up your threads and may be piecing on your machine one day and then quilting the next, it’s important to have a good grasp of how to handle your machine’s tension issues.

Thread tension on most sewing machines is accomplished by applying pressure to one side of a spring which presses on a tension disk.  Tension is applied to the thread as it passes between a pair of tension disks.  This tension is either adjusted manually or electronically through a computer-controlled electromagnet (depending on your sewing machine).  Increased pressure on the tension spring increases the thread tension.  When a 50-weight thread is replaced by a heavier 40-weight thread, the increased diameter of the thread pushes the tension disks further apart, increasing pressure on the tension spring.    By increasing or decreasing the diameter of the thread, we increase or decrease the thread tension.  If the tension is too high, it damages the thread and the thread breaks.  If the tension is too low, the thread will loop on the back of the fabric.  When you change out thread, and the new thread is a different weight than the preceding one (or a different brand), always test out your stitching on a scrap of fabric before piecing or quilting again.  You may find you need to make a few tension adjustments. 

In closing, remember the most common method to gauge the diameter of thread is the weight system.  This isn’t a perfect system, but it is the most common and most easily understood by quilters and other sewists.  However….

You must always be the final judge in what kind of thread you use and for what purpose.  To find your favorite piecing thread, try a small spool of two or three different brands.  Sew a ¼-inch seam and a scant ¼-inch seam with each.  Press each seam to the side and remeasure.  Which thread gives you the truest seam measurement once it’s pressed?  Run your finger along the seam.  Which thread feels best?  As you answer these questions, you’ll find your favorite piecing thread.  And your second favorite (because you always need a backup).

As far as quilting thread goes, the first question to ask is do you want your stitches to show, or do you want them to kind of melt into the background?  If you want them really nondescript, a higher weight thread (as high as 100-weight) may be exactly what you want.  If you’re a confident quilter and you want your quilting to shine more than the piecing or applique, start with a 40-weight and go lower if needed.  If you want something in the middle, try a 50- or 60-weight.  Want a sheen?  Try polyester.  Want traditional?  Go with the all-cotton.  Above all else, before you put one quilting stitch in that quilt sandwich, unspool about a foot of each thread under consideration and audition it on your quilt top.  Go about this just as seriously as you auditioned your fabric.  You may find you want some of the quilt quilted in one kind of thread and the other parts of the quilt quilted in another.  And that’s perfectly okay.

I know this has been a long blog, and thanks for hanging in there with me until the end.  Believe me, the kind of thread you use is one of those details which truly make a difference in both your quilt and your quilting process.

Until next week, the details really DO make a difference!

Love and Stitches,

Sherri Fields   

12 replies on “Threading the Needle”

Thanks for a great article, Sherri! I, too, am a fan of Invisifil thread, especially for ditch quilting, as I don’t like invisible thread. I order much of my thread online, and suggest investing in color cards for the most-used types of threads. The cards have actual samples of the thread. So much better than trying to discern a color from a computer monitor! My other favorite thread is 100 weight silk, either from Superior or YLI. I use it for quilting, and love its subtlety.

Color cards are a wonderful idea and I forgot to mention them in my blog. I have several of them from Aurifil and Superior. They do come in handy. I order about 90% of my thread (especially thread for the longarm) on line. It’s always a challenge matching up colors. The 100 weight silk — do you use that in your machine or long arm or is that for hand quilting?

I use the 100 wt. silk thread for hand applique and in my domestic sewing machine for machine quilting. It needs a #60 or #70 needle. I took a class years ago from Diane Gaudynski, and she highly recommended the silk thread, along with wool batting. It’s great for dense background quilting, as there is little thread buildup.

I have never tried silk thread for machine quilting. Currently my thread drug of choice is Superior Threads Micro Quilting thread, which is 100-weight polyester. I will, however, take your recommendation under advisement and try it. Right now I am quilting two Halloween quilts for the grand darlings and I am using glow in the dark thread for the first time. It’s a ton of fun!

Have you tried Presencia sewing thread? It was recommended to me by quilter/teacher Kelly Ashton who also uses it for longarm quilting. It is a long staple 3ply thread made of 100% Egyptian cotton grown in Giza Valley, home of the highest grade cotton in the world. I prefer it to Aurifil. I enjoy your weekly emails.

Rule of thumb, if you have thread on those old styrofoam or wooden spools, toss it or put it in a pretty jar to look at. It’s too old to sew with. From everything I’ve read, today’s thread can last for years and years before it becomes unviable. There was a wild rumor a few years ago that storing thread in the refrigerator will make it last longer. That rumor has been de-bunked. All it does is take up room you need for more ice cream.

I’ve been picking up Wonderfil Efina thread when I can get it. I took a class with Irene Blanck a couple of years ago and she recommended it. It’s 60wt and melts like butter into the turn under allowance for my applique.

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