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Demonstrations>Getting Started>Fun
With Bias
The Fear of Bias
Roberta Carr in her text Couture:The Art of Fine Sewing,
speaks about 'bias':
"The fear of working on 'the
bias' was ingrained in many of us at an early age. Some
sewing teachers spoke of it as 'the enemy', never to be
understood and to be kept at a distance. The bias is not
a disease - it is a grain of cloth that when respected,
can be used to advantage to produce remarkable results."
She is specifically talking about couture sewing in which
bias is used to achieve some dramatic effects. Most of you
are probably more interested in how I can possibly make working
with bias into a good idea for historic tailoring, let alone
a 'fun' thing do work with. Bias is one of those things that
can be your best friend or worst enemy - no in betweens. Those
of you who have heard the term but don't quite understand
to what it is referring have, in all likelihood, already run
afoul of the Bias Beast. Let's begin with a quick definition
of the term 'bias' and then we'll go on from there.
What is 'Bias'?
At its most basic, fabric is a matrix made up of warp and
weft threads. The warp threads are the long threads that are
rolled through the sheds of the loom during weaving. The weft
thread runs back and forth, in and out of the various warp
threads. This whole operation makes a grid, with warp threads
running along the 'y' axis and weft threads running
along the 'x' axis. The selvedge edge that runs along
both edges of the piece of fabric run along the y axis, parallel
to the warp or 'with the warp'. The selvedge edge is the best
landmark for figuring out the 'grain line' of the fabric.
Common grain line runs parallel or 'with' the warp threads.
When we cut our pattern pieces out of the fabric, it is important
to place the pattern pieces with the 'straight of grain' or,
to be more specific, to make sure that the pattern piece has
the bulk of itself along the straight of grain. This does
two things. First it makes sure that there is as little bias
as possible in the cut piece. Second, this aligns the piece
with the long, warp threads in the fabric. This is a modern
couture thing but I've seen much evidence for this treatment
in the Tailor's pattern books from period. Without fail, the
pattern pieces are laid with the straight of grain. If the
fabric has a nap, the nap is always facing down. This is contrary
to theatre costuming in which the nap always runs up to catch
the light.
Bias cuts, and more specifically, true bias cuts happen when
we cut the fabric at a 45 degree angle across the warp and
weft threads. This compromises the matrix of the fabric and
allows 'stretch'. This is where we can get into real trouble
if we don't pay attention to how our pattern pieces are cut
out. Different values of 'stretch' when they are planned for,
are a good thing. Stretch where you don't want it creates
wrinkles and ill fit with virtually no way to remedy the situation
without removing the piece and re-cutting it.
Rectangular construction methods rely on straight of grain
for most of the pieces in a pattern but the fit in such is
invariably accomplished by use of bias engineering.
Fitted clothing, however, has pattern pieces that regularly
violate the bias; from actual true bias to non-true bias.
This is essential in getting those fitted pieces to actually
fit but, as I've mentioned, if you don't know how the fabric
is going to behave, you can get into trouble. The basic rule
is that the closer to true bias a cut is, the more it will
stretch. We'll talk more about this when we discuss sewing
methods.
Historical Fun With Bias -
Take a look at the pattern below:
Pattern #147, from A Tailor's Pattern Book by François de
la Rocha de Burguen,
©1998 The Victoria and Albert Museum, all rights reserved.
The red arrow represents the warp line or grain line of the
fabric. This is known as 'lengthwise grain'. The green arrow
represents the weft line of the fabric. This is known as 'cross
grain'. The blue arrow represents true bias of the fabric.
This particular pattern is from a Tailor's Pattern Book from
1618. The fabric is folded, selvedge edge to selvedge edge,
thereby cutting two of everything. The pattern pieces are,
from left to right: pant leg, doublet skirts front and back,
doublet back, collar pieces and doublet front, sleeve, and
other pant leg.
As you can see, there is a great deal of bias cutting going
on here in these complicated shapes. However, very careful
attention has been paid to those parts of the clothing where
the stretch of bias is unwanted as well. This is controlled
for by placing those spots on the straight of grain when cutting.
For example, the inseam of the pant leg, which is the only
straight cut on the pant leg, is cut almost on the true bias
of the fabric. Inseams are a good place for stretch so this
is a good thing. However, we would not want the front of the
doublet to stretch out and get all wobbly so the majority
of that line is on straight of grain. The bottom of that line
is place somewhat on the bias which would stretch to accommodate
the curve of the stomach. Same goes for the doublet skirts.
The fronts are place on the straight of grain, the sides almost
on true bias.
Take a look at the rectangular pattern below:
This is a rectangular pattern for a Central Asian coat from
about the same time period as the first pattern. Almost every
piece is cut or ripped on the straight of grain. The exceptions
are the side gores, the under gores and the front flap. All
these pieces have one cut on the bias. When the construction
phase is reached, as illustrated above, the bias cuts for
the side gores and the front flap are mated with straight
of grain cuts on the body piece. This accomplishes two things.
First, it makes sure that the stretch of the bias cut only
stretches so far and doesn't become wobbly. Second, it forces
the fabric to lean and stretch around the body, thereby fitting
it to the curve of the body. The under gore, however, has
the bias cuts sewn together. One of the biggest reasons for
this is that the area under the arm requires as much stretch
and give as possible to make it comfortable.
The Great Bias Binding Debate -
Historical edge binding? Was it cut on the bias or wasn't
it? That's a really good question and is not always easy to
answer. As a general rule, it was not cut on the bias. Bias
was a known and used term in period but is a very wasteful
way of doing things. Most of the time, in period, a real distinction
is made between cutting a strip on the bias and embellishing
it on the bias. To cut it on the bias means just that. Embellishment
on the bias means that the embellishment, most often linear,
was done at a 45 degree angle to give the strip a candy stripe
look.
Most of the historical pieces I've been able to look at have
pieces of edge binding that were either straight of grain
or not true bias, made up of scraps left over from the initial
cutting of the garment. None of the Tailors books I've seen
have any reference to bias cut binding and only two have references
to bias cut garments, which take advantage of woven stripes
in the material, to form chevrons in the finished garment.
Almost all do make reference to using the 'cabbage' or scraps
as binding.
Two specific historical examples show edge binding in enough
detail to make the determination that it was cut on the straight
of grain. The first example is the sleeved pair of stays of
pink watered silk in Fashion in Detail by Avril Hart
and Susan North. This pair of stays is English and has been
dated to 1660. The pictures in this text are so good that
you can see the grain line of the edge binding. It is clearly
on the straight of grain. The second example is from the text
Costume Close-Up: Clothing Construction and Pattern 1750
-1790, by Linda Baumgarten & John Watson with Florine
Carr. To quote:
"Today, we use strips of
fabric cut on the bias to bind edges. In the eighteenth
century, bindings were cut on the straight of the goods.
Certainly the extreme waist of material that results from
cutting bias binding would have been unacceptable in the
1700s. In fact, it may not have occurred to eighteenth-century
seamstresses and tailors to try it. It is difficult to manipulate
straight-grain binding around curves with a machine. When
working by hand, one can make adjustments and ease the textiles
together."
In other words, bias binding is fairly easy to sew onto a
garment with a sewing machine. You can stretch or not to fit
around corners as you go. Straight of grain binding almost
always has to be sewn on by hand. Corners and curves need
to have the strip eased around them as you sew. While only
one example is in the scope of this website, both point to
what I believe is evidence that bias
How to Make Bias Work for You -
One of the first things I do when I draft out a pattern is
to mark the grain lines. I follow three basic rules in order
to find a good grain line for each piece. First, I look at
the position of the piece and try to put the grain line parallel
with the body or on the vertical line. If the piece is a sleeve,
I run the grain with the length of the arm. Second, if I am
going to be engineering the pattern on purpose to use the
bias, I look to see if I can sew the bias cut to a straight
cut or a similar bias cut that will work with the various
stretches. Bias seams curve very nicely around bodies and
when planned for and done correctly, can virtually eliminate
wrinkles and improve the fit of a garment. Lastly, if there
is no real landmark, I always default to the vertical or with
the warp.
When sewing bias cut seams together, it is very important
not to stretch them in any way. I don't usually pin these
seams together, preferring instead to adjust as I go. You
can also use the feed dogs of your sewing machine to slightly
gather the bias cut side as you sew it to a less biased or
straight cut side. If both sides are bias cut, the convex
side should be on the feed dogs and the concave side should
be on top so that you can fuss with it as you go.
As far as bias binding goes, I use it every chance I get.
My favorite method is to make up the bias first, prior to
starting anything else so that I can simply grab it when I
am ready. This involves cutting the strips and sewing them
together, end to end. Sometimes I'll press one or both sides
and sometimes, I'll not worry about it. Often, I'll sew the
binding on first and then press it over in preparation for
tacking down.
There... that wasn't so bad... Bias is your friend.
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