Topics

Polyester Thread

The Polyester Thread Buying Guide helps customers get the right thread for their needs. Our approach is to help you decide if polyester is the right thread for the job, identify which sizes (thicknesses) should be used, and finally pick the color and spool size that works. We have polyester thread in eleven sizes, over 100 colors, and putups ranging from small spools priced around $10 to discounted cases.
Polyester Thread Uses - Polyester thread looks, feels, and sews like nylon. You cannot tell the difference just by looking at the thread and differences in many technical specifications are insignificant. This means that polyester works just as nylon in most applications including: upholstery, leatherwork, auto interiors, banners and flags, sports gear, dog collars, horse saddles and tack, knife sheaths, gun holsters, fishing lures, and brief cases.

Polyester is a better choice when there is prolonged exposure to sunlight, mildew, bleaching, acids, or alkalis. These include: marine and outdoor upholstery; tarpaulins and pool covers;  flags and banners left outside; and convertible tops especially in the Southwest. It is important to distinguish between prolonged and occasional. There are many things that are taken outside but not left outside such as tents, clothing, sports gear, and most leatherwork. In these cases nylon and polyester work equally well.

Polyester thread does not provided the ultimate sunlight (UV) resistance. Brands like Sunbrella and Tenara come with replacement guarantees and UV treated nylon and polyester threads will out perform regular polyester. None of this matters if the material sewn is not equally bleach and sunlight resistant. After all, the material makes up at least 90% of the content and cost of the item that is being sewn.

There are times when polyester thread should not be used:

Spun Polyester - Most garments are sewn with some type of spun polyester. This kind of thread is a thin strand of polyester thread wrapped in a cotton outer layer. It is very inexpensive and has a soft, cotton-like texture.

Fire retardant garments and gear -  Polyester thread sticks at 440F to 445F and melts at 483Fahrenheit. First responder garments and gear and some high temperature conveyer belts require much more fire retardance. Use Kevlar and Fire Retardant in these situations. All are heat resistant to 700F and does not melt.

Critical strength requirements - Polyester is strong but  Kevlar Thread is about twice as strong. For example, size 92 polyester as a 14.5 pound tensile strength; the same size Kevlar has a 30 pound tensile strength. Kevlar's downside is that it costs about five times more than polyester and only available in yellow. Consider using heavier weight polyester or double-stitching to meet strength requirements.

Polyester Thread Size -  Thread size refers to the thread's approximate thickness. Thread is soft and spongy and its thickness cannot be accurately measured with calipers. The Commercial and Tex sizes on our site measure the weight of a fixed length of thread. For example, a 1,000 meters of Tex 70 weighs 70 grams. Having said this, the military includes thread thickness in their specifications and we include them in our Polyester Thread Specifications.

 

Thread size is important because it affects so many things:

When thread size increases...   When thread size increases...  

Thread diameter

Increases

Stitch visibility

Increases

Strength

Increases

Sewing machine size

Increases

Sewing heat and friction

Increases

Yards per pound

Decreases

Needle size

Increases

 

 

The material that you are sewing costs far more than the thread. In most cases (parachutes excepted) it is better for the thread to break than to have the stitches pull through the fabric. This means that the weight of the fabric, in ounces per square yard, is the best way to determine thread size. Here are size recommendations for fabric and leather.

Fabric Ounces Per Yard

Thread Size Range

Leather Ounces Per Yard

Thread Size Range

2 to 6 Ounces

15 to 33

1 to 8 Ounces

46 to 207

6 to 8 Ounces

33 to 46

8 to 12 Ounces

138 to 277

8 to 10 Ounces

46 to 69

12 to 16 Ounces

207 to 346

10 to 12 Ounces

69 to 92

Multiple Layers

207 to 346

12 to 14 Ounces

92 to 207

   

There other things to consider. You may use a thinner thread because your machine cannot handle a heavier thread. Or, you may choose a thicker thread because you want stitches to stand out.

Bonded or soft? - Bonded means that a thread has a coating that reduces needle heat and fraying. It makes thread stiffer and about 5% thicker than soft thread that does not have a coating. The choice between bonded and soft depends on how the thread is going to be used and thread thickness. Here are our recommendations:

Sewing Application

Recommendation

Machine sewing lightweight
thread sizes 15 to 46

Lightweight thread sizes generate little needle heat
and are unlikely to fray. Bonded and soft thread work
equally well.

Machine sewing thread sizes
69 and higher

Bonded thread is strongly recommended

Hand sewing

It does not matter if you use bonded or soft thread.

Wrapping and gluing

Soft thread is preferred because bonded thread often
repels glues and adhesives. You can soak a bonded
thread in alcohol to remove the bonding.

Other non-sewing applications
such as hanging and reinforcing

Finish does not matter in most cases. Bonded thread
is better if it is going through a narrow tube.

Spool Sizes - We sell most of our polyester thread in 2 Ounce, 4 Ounce, and 16 Ounce (1 Pound) spool sizes or putups. The smaller putups cost more per ounce than the larger ones. But, they are a better choice for one-time jobs, casual sewers, people who need a stash of many colors, and experimenters.

Polyester thread is sold by weight (ounces, pounds) - not yards. This is because the number of yards-per-pound decreases as thread thickness increases. Selling by weight means prices for a given size spool are about the same across most thread sizes..

Industry norms allow polyester thread spool weights to vary by plus/minus 10% from the stated nominal weight. This means that customers get slightly less or slightly more thread than the nominal weight shown on our site. The table on the right shows our nominal weights and the thread-weight range ( including the spool's weight ) for various sizes.  When spools fall within these ranges we do not charge for overages or refund underages. Here are the weight ranges we use:

Nominal Weight Nominal Minimum Nominal Maximum Nominal Weight Nominal Minimum Nominal Maximum

2 Oz

2.6 Oz

4.5 Oz

8 Oz

8.0 Oz

10.5 Oz

4 Oz

4.6 Oz

5.9 Oz

12 Oz

10.6 Oz

15.5 Oz

6 Oz

6.0 Oz

7.9 Oz

16 Oz

15.6 Oz

19.9 Oz

Spool base width and height vary with the putup:
Putup Base Height Putup Base Height Putup Base Height
 2 and 4 Oz 2.5" 4.5" 8 Oz 3.5" 5.5" 12 and 16 Oz 4.5" 7.5"
 

Elongation - Polyester thread stretches about 25% before it breaks. This means that 10 yards of nylon thread will be 12.5 yards when it snaps. This stretchiness is a good thing in most cases. It allows the seams to expand and contract with the material and avoids puckering and breakage. Polyester's stretchiness may not be desirable in some hanging, reinforcing, or wrapping applications. When this is so, consider less stretchy threads such as cotton, spun polyester, or Kevlar.

Twist -  Most of the polyester thread on our site is left twist (also called Z-twist) because that is what single-needle machines made for the U.S. use. We have a few, clearly marked, right twist (also called S-twist) thread for double-needle machines. A thread's twist makes no difference when it comes to hand-sewing and non-sewing applications.

Polyester Thread Specifications

Size

Tex

15

30

45

70

90

135

210

270

350

410

600

Government

A

AA

B

E

F

FF

3-Cord

4-Cord

5-Cord

6-Cord

8-Cord

Strength

                     

Pounds

1.5 3.0 7.0 11.0 14.5 21.0 31.0 44.0 53.0 73.0 98.0

Kilos

0.7 1.4 3.2 5.0 6.6 9.5 14.1 20.0 24.1 37.7 44.5

Thickness

                     

Inches - decimal

0.0047 0.0070 0.0080 0.0107 0.0124 0.0152 0.0186 0.0231 0.0258 0.0283 0.0330

Inches - thousandths

5/1000 7/1000 8/1000 11/1000 12/1000 15/1000 19/1000 23/1000 26/1000 28/1000 33/1000

Millimeters

0.1194 0.1778 0.2032 0.2718 0.3150 0.3861 0.4724 0.5867 0.5867 0.7188 0.8382

Needle Size

                     

U.S.

10-12

12-14

14-16

16-18

18-20

20-22

22-24

24-26

26-28

28-30

30-32

Metric

70-80

80-90

90-100

100-110

110-120

120-14-

140-180

180-220

220-260

260-330

300-360

Nominal Yards

                     

2 Ounce Spool

3,750 1,525 1,188 750 563 375 263 187 163 125 79

4 Ounce Spool

7,500 3,050 2,375 1,500 1,125 750 525 375 325 250 158

8 Ounce Spool

15,000 6,100 4,750 3,000 2,250 1,500 1,050 750 650 500 315

12 Ounce Spool

22,500 9,150 7,125 4,500 3,375 2,250 1,575 1,050 975 750 473

16 Ounce Spool

30,000 12,200 9,500 6,000 4,500 3,000 2,100 1,500 1,300 1,000 630
Thread Size and Machine Type - As thread size increases, a more powerful machine is needed to push the thread through the material.

Size

Home

XXXXXX

XXXXXX

XXXXXX

XXXXXX

             

Commercial

     

XXXXXX

XXXXXX

XXXXXX

XXXXXX

       

Heavy Duty

         

XXXXXX

XXXXXX

XXXXXX

XXXXXX

XXXXXX

XXXXXX

Thread Size / Stitch Visibility - Do you want the stitches noticed?

Size

Inconspicuous

XXXXXX

XXXXXX

XXXXXX

XXXXXX

 

           

Noticeable

       

XXXXXX

XXXXXX

         

Stands Out

         

XXXXXX

XXXXXX

XXXXXX

     

Focal Point

             

XXXXXX

XXXXXX

XXXXXX

XXXXXX

Polyester Thread Uses / Size Ranges - Best size depends on material thickness, seam strength, stitch visibility and sewing machine size.
xxxxx

Size

15

33

46

69

92

138

207

277

346

415 554

Amplifier Cover

    xxxxx xxxxx xxxxx xxxxx          

Archery Case

      xxxxx xxxxx xxxxx          

Athletic Mats

      xxxxx xxxxx xxxxx xxxxx        

ATV Cab Enclosures

      xxxxx xxxxx xxxxx xxxxx        

Automobile

                     

Convertible Tops

        xxxxx xxxxx xxxxx        

Covers

      xxxxx xxxxx xxxxx xxxxx        

Upholstery

      xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx  

Awnings

                     

Lightweight (bed canape)

   

xxxxx

xxxxx

             

Middleweight (patio)

       

xxxxx

xxxxx

xxxxx        

Heavyweight (hotel)

         

xxxxx

xxxxx xxxxx xxxxx xxxxx xxxxx

Size

15

33

46

69

92

138

207

277

346

415 554

Backpacks

   

xxxxx

xxxxx

xxxxx

xxxxx xxxxx        

Banners and Flags

                     

Lightweight (mostly indoor)

  xxxxx xxxxx xxxxx xxxxx            

Middleweight (most common)

        xxxxx xxxxx xxxxx        

Heavyweight (outdoor flags)

         

xxxxx

xxxxx xxxxx xxxxx xxxxx xxxxx

Boat

                     

Upholstery

   

xxxxx

xxxxx

xxxxx

xxxxx

         

Covers

     

xxxxx

xxxxx

xxxxx

xxxxx

       

Size

15

33

46

69

92

138

207

277

346

415 554

Bookbinding

      xxxxx xxxxx xxxxx    

Canvas

                     

Lightweight (artwork)

xxxxx

xxxxx

xxxxx

               

Middleweight (tents)

   

xxxxx

xxxxx

xxxxx

xxxxx          

Heavyweight (covers)

       

xxxxx

xxxxx

xxxxx

       

Carpentry Aprons

xxxxx xxxxx xxxxx                

Cat Collars and Leashes

xxxxx

xxxxx

xxxxx

               

Cell Phone Covers

   

xxxxx

xxxxx

             

Church Pews

    xxxxx xxxxx xxxxx

xxxxx

         

Corn Hole Bags

    xxxxx xxxxx xxxxx xxxxx          

Cowboy Boots

                     

Decorative Stitching

xxxxx xxxxx xxxxx                

Uppers

   

 

xxxxx

xxxxx

xxxxx

xxxxx

       

Soles

            xxxxx xxxxx xxxxx xxxxx xxxxx

Size

15

33

46

69

92

138

207

277

346

415 554

Curtains

 

xxxxx

xxxxx

xxxxx

             

Lightweight (Shower)

  xxxxx xxxxx

xxxxx

             

Middleweight (Drapes)

      xxxxx xxxxx

xxxxx

         

Heavyweight (Stage)

                     

Cushions

     

xxxxx

xxxxx

xxxxx

xxxxx

xxxxx

     

Decorative Stitching

   

xxxxx

xxxxx

xxxxx

xxxxx

xxxxx

       

Dog

                     

Beds

  xxxxx

xxxxx

xxxxx

xxxxx

xxxxx          

Collars

    xxxxx xxxxx

xxxxx

           

Harnesses

    xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx      

Leashes

    xxxxx xxxxx xxxxx xxxxx xxxxx        

Drum Covers

    xxxxx xxxxx xxxxx            

Duffel Bags

   

xxxxx

xxxxx

xxxxx xxxxx          

Size

15

33

46

69

92

138

207

277

346

415 554

Event Displays

    xxxxx

xxxxx

xxxxx

           

Fishing Tackle

xxxxx xxxxx xxxxx                

Fly Tying

xxxxx xxxxx xxxxx                

Garments

xxxxx

xxxxx

xxxxx

xxxxx

             

Gloves

                     

Casual (Dress)

xxxxx xxxxx xxxxx                

Work (Gardening)

  xxxxx xxxxx xxxxx              

Guitar / Instrument Straps

   

xxxxx

xxxxx

             

Gun

     

xxxxx

xxxxx

xxxxx

         

Cases

      xxxxx xxxxx xxxxx xxxxx        

Holsters

     

xxxxx

xxxxx

xxxxx

xxxxx

xxxxx xxxxx xxxxx xxxxx

Gymnastic Mats

     

xxxxx

xxxxx

xxxxx

xxxxx

       

Size

15

33

46

69

92

138

207

277

346

415 554

Hammocks

          xxxxx xxxxx        

Hemming

xxxxx xxxxx xxxxx                

Home Sewing

xxxxx xxxxx xxxxx xxxxx              

Horse

                     

Blankets

      xxxxx xxxxx xxxxx          

Saddles and Tack

          xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx

Hunting Blinds

    xxxxx xxxxx xxxxx xxxxx          

Inflatables

    xxxxx xxxxx xxxxx xxxxx          

Knife Sheaths

      xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx  

Laptop / Ballistic Cases

    xxxxx xxxxx xxxxx xxxxx          

Leather

                     

Lightweight (Jackets)

  xxxxx xxxxx xxxxx              

Middleweight (Belts)

      xxxxx xxxxx xxxxx xxxxx        

Heavyweight (Boots)

          xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx

Size

15

33

46

69

92

138

207

277

346

415 554

Loading Dock Seals

          xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx

Log Carriers

        xxxxx xxxxx xxxxx        

Luggage

      xxxxx xxxxx xxxxx xxxxx        

Marine Upholstery

      xxxxx xxxxx xxxxx xxxxx        

Motorcycle

                     

Saddlebags

      xxxxx xxxxx xxxxx xxxxx        

Seats

      xxxxx xxxxx xxxxx xxxxx xxxxx      

Tank Bibs

    xxxxx xxxxx xxxxx xxxxx          

Outdoor Furniture

                     

Covers

    xxxxx xxxxx xxxxx xxxxx          

Upholstery

      xxxxx xxxxx xxxxx xxxxx        

Webbing

  xxxxx xxxxx xxxxx xxxxx            

Place Mats

  xxxxx xxxxx xxxxx              

Pool Covers

        xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx

Pool Table Covers

    xxxxx xxxxx xxxxx xxxxx          

Size

15

33

46

69

92

138

207

277

346

415 554
Restaurant                      

Bar Stools

    xxxxx xxxxx xxxxx            

Booths

      xxxxx xxxxx xxxxx xxxxx        

Chairs

  xxxxx xxxxx xxxxx xxxxx            

RV Covers

        xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx

Sails

                     

Lightweight

  xxxxx xxxxx xxxxx              

Middleweight

    xxxxx xxxxx xxxxx xxxxx          

Heavyweight

          xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx

Sand Bags

    xxxxx xxxxx xxxxx xxxxx xxxxx        

Snowmobile

                     

Covers

      xxxxx xxxxx xxxxx          

Seats

      xxxxx xxxxx xxxxx xxxxx        

Spa Covers

      xxxxx xxxxx xxxxx xxxxx        

Size

15

33

46

69

92

138

207

277

346

415 554

Tailoring

xxxxx xxxxx                  

Tarpaulins

      xxxxx xxxxx xxxxx xxxxx        

Tents

                     

Lightweight (Camping)

    xxxxx xxxxx xxxxx            

Middleweight (Party)

        xxxxx xxxxx xxxxx        

Heavyweight (Circus)

            xxxxx xxxxx xxxxx xxxxx xxxxx

Trampolines

          xxxxx xxxxx        

Umbrellas

                     

Rain

  xxxxx xxxxx xxxxx              

Patio

      xxxxx xxxxx xxxxx xxxxx        

Vinyl

                     

Lightweight

  xxxxx xxxxx xxxxx              

Middleweight

    xxxxx xxxxx xxxxx            

Heavyweight

        xxxxx xxxxx xxxxx xxxxx xxxxx    

Wallets

  xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx    

X-Ray Aprons

    xxxxx xxxxx xxxxx xxxxx          

Copyright © 2016 Weaverville Thread, Inc... | Ecommerce Shopping Cart Software by Miva, Inc.