Stitch Length – Yes, it matters
I get a lot of questions about stitch length. What is the ideal stitch length? It depends on your thread. How do you know you have the right stitch length? You’ll see it! I have a short, informative post on stitch length.
I am talking about free motion quilting here, although the principle would be the same if my feed dogs were up. Because I am free motion quilting, my feed dogs are down and the combination of machine speed and how fast I move the fabric determines my stitch length.
So when free motion quilting, it does not matter at all what I set my machine’s stitch length at – those feed dogs are below my stitch plate doing their thing and NOT affecting my stitch length.
The ideal stitch length will depend on how thick your thread is (“weight”), as well as how long your stitch length is.
Here’s a quick review of thread weight (thickness): it is expressed in a number and the higher the number, the skinnier the thread.
100 weight thread = super skinny
12 wt thread = super fat
Looking at stitch length first:
For this first sample, I used a thick 12 wt Wonderfil Spagetti and a Superior Threads 100 wt needle. In all of my samples I kept to Quilters Select Perfect Cotton Plus, a 60 wt poly core with a cotton wrap in my bobbin.
The top line is good stitch length, the second line has stitches that are too tiny and the third has stitches that are too long. What you are looking for is a pretty little arch of thread showing, like in the first line. Each stitch is well defined.
The second line of stitching has tiny stitches. The beauty of the thread does not show, the stitches are piled up on top of each other and just kind of all run into each other. The sheen of the thread cannot show because there is not enough of the thread showing.
The third line of stitching has long stitches. The thread kind of flops around in between stitches. You don’t see a pretty little arch because it’s flat to the surface and not tensioned enough to show the beauty of the thread.
You can tell the right stitch length for any thread by looking for well defined stitches and a pretty little arch for each stitch.
Looking at a mid weight 60 wt Superior Threads Bottom Line, a 60 wt poly with a 70 needle:
Again, top line good stitch length, middle line has tiny stitches and bottom line (no pun!), the stitches are too long.
And here we go with a thick 100 wt Wonderfil’s Invisifil with a 70 needle:
Same order of stitch length.
And in summary, here is a great comparison with the best stitch length for all 3:
Can you see how the thicker thread on top needs a longer stitch to catch its beauty while the thinner threads need a shorter stitch? The best stitch length will vary based on the thickness of the thread.
I tend to use 100 wt silk thread a lot because I love its sheen and beauty. In most classes I ask students to bring a mid-weight thread, a 50 or 60 weight thread. They will look at my samples with skinny 100 wt thread and try to mimic that tiny stitch length with their comparatively thick thread. That’s not going to work – the stitches will pile up on each other and rob the thread of its beauty.
Don’t fret about this – you will see good stitch length; your eye will know it!
And Good News – I am developing a laminated one-page summary of the best practices for your free motion set up that will include a thread and needle pairing chart as well as a ton of other useful information. Stay tuned!
I’ll share at:
Nina-Marie’s Off the Wall Friday
and
Finished or Not Friday.
Karen Scribner says
Seems to me stitch length should only matter if you’re trying to do something decorative. A structural stitch length needs to be 12 to 15 stitches per inch to hold the seams of a quilt block and to keep it from pulling out at the edges.
Jenny Lyon says
Exactly, you’re correct . But I am talking about free motion quilting, which by definition would be decorative. Functional stitching has entirely different parameters and I’d never be stitching seams with thin silk thread or super thick cotton. Free motion has it’s own set of requirements.
Lynne MacDonald says
THANK YOU in advance for preparing the thread and needle chart!
Jenny Lyon says
You’re welcome! Stay tuned!