Knitting Stitches

In this segment, we discuss the design
of the fabric, and the basic

stitches that make up knits.

There are only three types of loops or
stitches possible in weft knitting:

knit, tuck, and float.

Let's take a look at the first one,
the knit stitch.

If every needle is fed a yarn and goes
through the basic knitting cycle,

the product is referred
to as single jersey.

All loops are knitted,
and all loops look exactly alike.

Look closely at this drawing
of a regular knit loop.

The length of yarn in that loop
is called the stitch length.

Notice how each loop has what can
be identified as legs and a crown.

The fabric at the left is technically
the face side, and the stitches

have an overall vertical appearance.

On this side, you see primarily
legs rather than crown.

The fabric at the right is technically
the back, which takes

on a horizontal appearance.

In this view, you see mainly crowns.

Referred to as a jersey stitch,
stitches arranged in this pattern have

a distinctly different look
and feel from the face to the back.

Another type of stitch is referred to as
the tuck stitch, because one yarn

is tucked behind another and hides.

The pattern on the left shows
the technical face for a tuck stitch.

Follow the green shaded course of yarn
across the pattern, and it looks like

a loop has been tucked behind another.

The pattern on the right shows
the technical back for a tuck stitch.

From the back, the tuck is
more visible to the eye.

How is a tuck stitch made?

During the tuck cycle, at feed one,
the needle moves up from its rest

position, and the old stitch that has been
formed is held and not

allowed to clear the latch.

Yet, the needle moves up far enough
to grab a second yarn,

which is put into a tuck position.

Both yarns are then kept
at the rest position.

The knit cycle occurs
with the next feed of yarn.

At this time, both yarns are cleared.

A new yarn is fed and pulled through both
the held and tuck loops,

forming a tuck stitch.

The stress caused by holding one elongated
stitch for an extra course causes more

length shrinkage, but less in width
than a regular knitted stitch.

The tuck loop makes the fabric wider
and thicker, and slightly less extensible.

What is the overall structural
effect of tucks on knits?

Tuck stitches can give
a fabric a cellular appearance.

Some people refer to this as mesh.

Tucks are the basis for pique,
typically used for golf and tennis shirts,

which need to breathe,
retain their shape, but have some stretch.

A wide range of pique constructions can be
made depending on the use

and frequency of tuck stitches.

The third type of stitch is the float,
which is also called a missed stitch.

The drawing on the left
is a technical face.

On the face, in the middle course of yarn
and middle wale, it looks like the machine

has hidden the colored yarn in the back.

It is not captured or knit
with any other stitch.

This is the float or missed stitch.

On the technical back,
you can see how the loop floats.

To produce the float stitch, on feed one,
a yarn is laid to rest behind

the hook of the needle.

The needle remains at the rest position.

It is not activated in the float cycle.

In the knit cycle, it is.

When a subsequent yarn is knit at the next
feed, the missed yarn floats

to the technical back of the fabric.

Loops can be made to float
over a series of wales.

To make the structure secure,
some float yarns can be tied into the

ground with a jersey or tuck stitch.

Float loops make the fabric more narrow
and less extensible because the floated

yarn is in a straight configuration.

Why would you produce a structure
with loops that float?

Floats are useful for pattern effects,
where some colors appear on the front

and others are hidden on the back.

This checkerboard pattern
uses gray and white yarns.

When the gray yarn knits,
forming a gray square on the front,

the white yarn floats to the back.

If you turn the fabric over and inspect
the back, the colors appear reversed.

A second use is to create surface effects
or change the performance of the fabric.

You can make loops float on one side
of the fabric,

then nap them to produce a fleece.

If not napped, these floats can
be used for esthetics or function.

You've just seen how three stitch
formations can be used in different ways.

All can be produced on warp or weft
machines, or used

for single or double knits.