This stitch has the fabulous ability to attach a LINING to KNIT FABRIC such that the lining doesn't rip out of the knit garment as soon as the knit garment is stretched.
TECHknitting has already given directions for lining a hat with a Polar fleece headband. which shows the overcast stitch in action, but this post shows the actual details of the stitch itself.
The illustration below shows a green lining being overcast stitched to a blue knitted fabric by a right handed sewer. (Click picture to enlarge.)
The close-up illustration below shows why this stitch works.(Click picture to enlarge.)
Attaching a lining to knitting is a challenge because lining is often made of WOVEN CLOTH, and woven cloth, as we know, does not stretch very much. Knitting, on the other hand, is extremely stretchy. The stitch chosen to attach such dissimilar fabrics has to--
1. hold the woven cloth in place, even when the underlying knitted fabric is stretching
2. not stop the knitted cloth from stretching
3. flexibly connect the woven cloth and the knitted fabric.
The overcast stitch gets a "A+" on all three factors. As stated in a previous post, the overcast stitch "tethers" the fabrics together rather than "nailing" them together. Look closely at the stitch in the close-up above and you'll see that the lining fabric is actually "hanging" from the knitted fabric. In other words, the overcast stitch is acting as a little string from which the lining is "swinging." This "swing" allows the lining to adjust to the stretch of the fabric.
As the final illustration, below, shows, there is also quite a bit of thread reserve in the overcast stitch--the path of the thread resembles a coiled spring, and this coil of thread has the reserve to stretch when stressed.
And yet...although the overcast stitch works the best of all the hand sewing stitches for attaching a lining, the reserve of thread in this stitch might not be enough to stop the thread from breaking when the knitting is over-stretched. You can mostly solve this problem by cutting the lining bigger than the garment, then sewing in the excess via little bite-sized bumps. This is called "easing in a lining." An example of easing in a lining is shown in the TECHknitting post mentioned earlier, about lining a hat, headband style, with polar fleece.
Good knitting--TK
This is part 5 of a 5 part series on hand sewing for knitters
Part 1: Starting off
Part 2: Starting off with a doubled thread
part 3: the running stitch
part 4: the back stitch
part 5: the overcast stitch (best way to attach lining fabric to knitting) (this post)
(You have been reading TECHknitting on: The over cast stitch--part 5 of "hand sewing for hand knitters.")