WTT!! (What The Thread!) Part 3

As promised here is the third and final installment of thread education!  Here I’ll talk about what thread terms mean.. some you may hear when reading or discussing thread, how thread is sized and and explaining the ‘finishes’ on a thread.

In case you missed it:

WTT!! Part 1
WTT!! Part 2

Sew let’s get started!

Thread Terms

I’ll start with what I ‘think’ you may have heard most often and move into less frequent terms.

Spun: This is when staple fibers are twisted into single strands.

Plying (or Ply): This is the process of taking 2 or more spun strands and twisting them together to form thread (or yarn as the case may be).

Textured Thread: This is just a process of crimping filaments to create different textures (bulky, softness, elasticity).

Core: This is as it suggests.  It’s the central fiber (polyester, nylon, cotton) in which a staple fiber is wound around.  The staple fiber or outer fiber could be the decorative metallic, could be polyester, etc.

Staple fibers: Natural fibers that are very short in size (think of the size of a cotton ball) – up to 2 inches.  Synthetic fibers that are double or more in size – up to 5 inches.

Monofilament, Multifilament, Triobal Filament: Monofilament are single extreme lengths of fiber (polyester, rayon, nylon, silk).  Multifilament is just as it suggests – several strands of extreme lengths of fiber together.  Triobal is a filament that has three sides for light reflection.

Thread Size

You may have noticed – especially if you’re into embroidery – there are different sizes of thread.  As you can imagine they are linked to the weight of the fabric you’re sewing into.  Light delicate fabric should have a light delicate thread (remember you want to match your thread to your fabric in most cases) and heavy weight fabrics such as jeans should have a thicker thread.

In my experience and research there doesn’t seem to be an industry standard.  But what I did find was some generalities. Thread2 Additionally, I had come upon a website selling thread that bespoke of Tex sizes.  What?

Here’s what I’ve found:

Weight: how many kilometers a thread has to be to weigh in at 1 Kilogram. The higher the number the lighter the thread.

Tex: the weight in grams of 1,000 meters. The higher the number the heavier and thicker the thread.

So here is a nifty generalized chart that should help you if size matters to you:

Fabric Type

Thread Weight

Tex Weight

Suggested Needle Size

Extra Light 120-180 16-24 60, 65
Light 75-120 24-30 70, 75
Medium 40-75 30-40 80-100
Medium Heavy 30-50 40-60 100, 110
Heavy 25-36 60-105 120, 140
Extra Heavy 11-20 105-135 140, 160

Please keep in mind this is a very generalized chart as there is no industry standard!  I have compiled this from reading many websites and books on thread.

Most important, just remember, in metric sizes, the higher the number the finer the thread.  In TEX standards, the higher the number the thicker the thread.

Now for our final section….


Finishes refers to the final touches on the thread before it is wound onto the spool.  It’s kind of like a helping hand for the proper type of lubrication.  For instance, serger thread is treated to enhance high-speed sewing – otherwise it would break constantly.

Bonded: This is a coating to keep polyester and nylon abrasion free and shred resistant.

Mercerized: This process adds flexibility to cotton or cotton covered polyester thread.  It reduces lint (important for your sewing machine!!), gives it strength and shimmer as well as making it useful for the dye process.

Glazed: This is actually only useful for hand sewing.  Any glazed thread will not bode well in your machine!  This process uses any number of chemicals and waxes to give thread a glossy smooth surface that reduces the amount of tangles and knots.

Gassed:  Simply a flash fire on thread to remove lint and give it a smooth look.

Soft: Untreated cotton.  In other words, nothing has been done to this thread so use it with caution because as we learned in Part 1, cotton is the weakest in the thread family.

And there you have it….all that I know about thread.  I do hope this has helped you in your learning process and adds a bit more to your arsenal of knowledge.

Let me know what you’d like to know more about!  I’m happy to share everything I know.  Don’t forget to check out the most recent tutorial on a Continuous Thread Dart.

WTT!! (What The Thread!) Part 2

Here is the second part and as promised, I’ll be writing about topstitch thread, rayon, fusible thread, metallic and other threads you may have heard of such as darning cotton. Before we get into that, I did want to mention one thing I had not mentioned in the previous article found here.

There are two very basic types of thread: Natural and Synthetic.  Natural thread comes from nature and include cotton, silk, wool, linen, rayon and hemp.  Synthetic threads are polyester and nylon.  It is worth noting here that natural fibers act differently in different climates, just like your clothes.  High UV can discolor dyed cotton, etc. Keep these in mind as I go through some of the more unusual thread below.

Types of Thread Part 2

Rayon: Think embroidery.  Because this fiber is not very strong and has no stretch, it is not useful for constructing much of anything really.  It is, however very soft, shiny and holds up to very high heat well.  Keep in mind this fiber doesn’t hold color very well. Uses: Embroidery floss and machine stitching.

Topstitch: Think visual wow.  This term is used for a heavier thread that can be made from any of the previously mentioned types of thread.  It’s also handy to use for hand stitching buttonholes on thick or heavy fabric. Uses: Bold statement topstitching on heavier fabric such as leather and vinyl, decorative topstitching and heavy duty utility stitching.

Fusible: Think basting.  This is a great thread that has come along recently that can eliminate basting is some projects.  It’s not stiff like some other fusible products and fuses with iron heat just like any other.  It is typically used in the bobbin and once heated will release the top thread, so make sure that top thread is a slippery thread (i.e. NOT cotton…use some sort of synthetic monofilament). Uses: Applique fusing, patchwork fusing, pocket fusing, or anything you need to hold temporarily in place to top stitch on or adjust for final stitching.

Water Soluble: Think ruffles. So this is another recent addition to the thread family and quite honestly it’s pretty ingenious.  Can you imagine no longer pulling basting stitches?  Baste. Sew. Wash. Done.  It can also be used for many of the same things that the fusible can be used for such as positioning applique’s, patchworks, and outer pockets.  Uses: basting and temporary placements prior to final stitching of anything.  Washes out.

metallic threadMetallic: Think decorative.  Who doesn’t like shiny?  It’s like the nail polish glitter of fabric!  The possibilities are endless for decorative stitching.  This can be used in a sewing or serger machine. A larger needle should be used and tension adjusted, so make sure you use a test piece of fabric to get it right before final stitching.  This thread can be used in all areas of a serger – upper looper, lower looper and any needle. Uses: Any decorative element you can think of from applique, shirring, flatlock, etc.

Darning Cotton: This is a very fine thread used for mending and darning.  This thread is used to recreate the weave of the hole that has been created.  This can also separate for even finer stitching. For darning socks and the like, you’ll want to use a darning egg or any household item that has the shape of a heel and will resist the poke of a needle.  For mending, flat surfaces work fine. Uses: hand stitching method of repairing holes or rips in any fabric.

Elastic: This thread is as it sounds.  Meant to be hand wound on the bobbin only.  It is used nearly exclusively for shirring or any place you want a good stretch. Uses: Professional look shirring.

That’s a wrap for today.  I’ll get part three in a few days.  I encourage you to stick with the basics if you’re just starting out.  Get comfortable with that and then move on to these.  Although, the water soluble thread I would encourage anyone to use.  I hope this has helped in your journey to thread usability.  The next and final section will clear up the rest.  Until next time….

Sew Jam On!


WTT!! (What the thread!) Part 1

My journey into sewing quickly brought me to quality and types of thread.  In groups I’m a member of for beginner seamstresses, that is a super frequent question…what thread do I use?  And sadly, there are those out there who have never thought about the difference and have sewn with crappy thread for years.  There is more to it than you’d think, so let’s go on a Sew Jam thread journey!

I need to say that I am not a fan of, nor ever will be a fan of, major department store (both general and hobby related) brand thread.  It’s cheap for a reason.  Might I add that you get what you pay for, I promise. With that said, let’s make our first stop.

Types of Thread:


Cotton: Think quilting.  This has little stretch and can break quite easily.  It can also produce a whole lot of lint which translates into bad mojo for your machine, especially if you buy cheap.  Uses: quilting, embroidery, heirloom and decorative and patchwork.

Polyester: Think everything!  It is has great elasticity.  It is one of the strongest fibers as well as heat resistant which means it can withstand the iron at high settings and is UV resistant. It’s quite popular because it can take on the appearance of cotton with polyester benefits or come in a nice sheen mimicking a silk look.  There are 4 different types of polyester thread used in the industry.  I won’t get into them here, since the differences are uses on Sergers (a different article all together), high speed industrial machines and long arm quilting machines.  If you really need to know what the four are, google it! Uses: general sewing, quilting and embroidery.

Cotton-wrapped Polyester: Think all purpose.  Polyester is a man made material or filament that covers cotton.  Therefore it will have all the characteristics of cotton with the benefits of a stronger, smoother polyester coating.  Uses: All purpose or general sewing.

Nylon: Think delicate.  Nylon is very similar to polyester in that it is man made from chemicals and is quit strong (think nylon leggings!). This thread is notable for it’s strength and flexibility which is important when your thread should be slightly stronger than the fabric it is securing for durability.  However, Nylon is not super UV resistant making Polyester a better thread for outdoor items and it is known to yellow over a long time period although it is rot resistant.  Additional it does not absorb liquid making it popular for under arm seams or sweaty areas of a body. Uses: light to medium weight synthetic fabrics, bonded nylon for upholstery and wooly nylon for serged seams, decorative stitching and rolled hems.

Silk: Think tailoring.  This is a fine strong thread for sewing silk and wool.  It’s also suitable for knits due to it’s elasticity.  It’s awesome for basting (although no one in their right mind would due to price … unless the garment is bridal, heirloom, etc) because silk will not leave a hole where stitched nor will it leave an indent or impression after ironing.  When I said think tailoring, I meant it.  This is a great natural fiber that will mold itself into the shaped tailored areas.  Uses: basting on any fabric, silk, wool, and knits.

These are the very basics.  When choosing your thread, you may hear some seamstresses tell you to match the fiber of the thread with the fiber of the fabric you’re stitching.  I tend to put a little more thought into it, such as: cotton clothing for children in which I’d use the stronger polyester thread for construction, or a project that is going to be subjected to high heat ironing, I’d use a high heat thread.  And, I may use more than one type of thread for a project!  Cotton on a neckline, polyester on the seams and wooly nylon for a nice soft hem.

Ok, let’s take a break in our journey to reflect a moment.  If you are a beginner, I have basically given you the ammunition you need to go out and get your thread on.  Alas, I am not done.  To avoid the deer-in-the-headlights look, I will end here.

In the next stop, I will cover: topstitch thread, rayon, fusible thread, metallic and other threads you may have heard of such as darning cotton.  In our final and third stop, I will clue you in to what some thread terms mean.. some you may hear when reading or discussing thread, how thread is sized and and explaining the ‘finishes’ on a thread.