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Frequently Asked Questions

About Thread Sizing

What size thread should I use for piecing?
Most modern machines like the 50/2 size, but some machines prefer the 40/2 (some older Singers or Kenmores, and most Viking machines).  Either are fine enough for piecing, though the 50/2 is a bit thinner.  For hand piecing, I recommend the 40/2 since it is stronger to hold up against the needle's eye.

What size should I use for quilting?
It all depends on the effect you want.  On the machine, I like the 50/2 for stitch-in-the-ditch work and for dense quilting like small stippling, or McTavishing.  When I want to see more of the quilting loft, the 40/2 is great.  It has a little more body than the 50/2, but is not too heavy a look.  This is also my recommended size for beginning machine quilters.  When you want to see the line, or if you are stitching on top of textured fabric, like flannel or brushed cotton, the 28/2 is wonderful.  It is similar to a 40/3, though just a little thinner.  It is not recommended if the design needs a lot of backtracking, since it will build up much faster.  Finally, the 12/2 is useful for some quilting, but you need the Topstitching 16/100 needle to work it in the machine.  It is nice for either a very rustic, or very contemporary look.  Use it when you want the thread to really make a statement, or for accent stitching.

For hand quilting, my first choice is the 28/2, but the 12/2 is also nice for a more robust look.  Don't try to get tiny stitches with the 12/2 - let it show. 

What size should I use for hand applique
The original recommended size for hand appliqué is the 50/2.  It is nice and fine, smooth running, and the twist is perfect so it won't come untwisted, or kink and become overly twisted.  It handles nicer than silk and is less expensive.  I offer the 50/2 colors in the mini-spools especially for appliqué enthusiasts.  220 yards per spool is a good size for appliqué.

More recently, Aurifil created the 80/2 applique and EPP thread.  It's even finer than the 50 wt and is excellent at hiding your stitches.  Currently, it is available in a small cherry wood spool of 300 yards and comes in 88 of the Mako cotton colors.

I don't understand sizes. Why is the larger number a thinner thread?
It is easy to be confused by thread sizes.  Many systems for defining sizes are used in the industry and adding to that is our habit of calling it all "thread weight".  AURIfil uses the NE system which is a count of the number of 840 yard hanks of single ply threads (called yarn in the industry) that it takes to weigh a pound.  This makes it a fixed-weight system since no matter the thickness, you are counting how many weigh a single pound.  It takes more of the thin hanks to equal a pound than it does the thicker hanks. 

Add to that is the ply count.  All of AURIfil's spun threads are two-ply, so two single 'yarns' are twisted together to create the final thread.  Any thread you use should list its yarn size and ply, but you can always untwist a small length of thread to see how many plies you have. 

You can compare threads of different ply counts by doing the math implied by the size notation.  50/2 = 25; 40/2 = 20; 50/3 = 16.667; 28/2 = 14; 40/3 = 13.33.  The larger the number, the finer the thread.