BIAS TAPE
You sometimes need to make your own bias tape.
You may want a width that isn't readily available, it
may be difficult to find tape that is sufficiently durable
for rough sewing, you might find making your own quicker
than waiting for mail order, and making it yourself is the
only way to get tape that matches your fabric.
Preparing the fabric:
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Most of the time, you will be using scraps that were
washed and pressed before you cut out the garment. If you
are buying whole cloth, take the usual precautions for the
sort of fabric you have bought.
If the fabric isn't stiff, it will be easier to handle
if starched. If you need to draw a thread or tear, do so
before starching. Threads get glued in when starched, and
tearing pops out the starch along the edge. Also, starching
serves to un-ruffle edges that have stretched during
tearing. (You can, however, re-touch torn edges with a
little diluted starch on a sponge.)
You don't need to cut along drawn threads until after
starching -- they usually remain clearly visible -- but it
is sometimes convenient to have the fabric already square
while ironing. On the other hand, some fabrics ravel if cut
before shrinking or starching. Study the piece in hand.
A light spritz with spray starch suffices for many
fabrics, but light cottons should be dipped in boiled
starch, preferably strong enough to make them act like
paper. Boiled starch can be bought pre-made in bottles at
the grocery store -- follow the directions on the label.
If bottled starch is not available, you can use corn
starch, potato starch, or whatever white powder your cusine
uses to thicken sauces. Put one tablespoon into a pint of
cold water, stir until the particles are evenly distributed,
and bring it to a boil while stirring constantly to prevent
lumps. (You can bring it to a boil in half the water, to
speed things up, then dilute it and bring it back to the
boil without paying such close attention.)
If something is wanted really, really stiff -- small
doilies to be hung by one corner, for example -- the
undiluted starch is used boiling hot, so that the thick
starch will penetrate.
For the usual case, add warm or cold water until there
is enough to cover your fabric, dip, slosh around, wring
out, hang to dry -- tumble driers and whipping winds remove
starch -- sprinkle, wrap in plastic overnight or until
evenly damp, iron. The fabric *can* be ironed straight out of
the starch bucket, but that's doing it the hard way, and it
won't come out as flat as dried-and-dampened fabric.
If it happens that you have a slick, waterproof surface
bigger than the freshly-starched fabric, pat the fabric out
nice and square, let it dry, and peel it off. Blocking is
easier than ironing, you don't waste time dampening, and it
is guaranteed flat. Blocking also leaves the fabric stiffer
than ironing does.
It is customary to starch when the fabric is still wet
from washing, as wet fabric takes starch more evenly than
dry fabric does.
To cut a hundred yards of one-inch bias tape
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from two yards of fifty-inch fabric,
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when seams are not a problem:
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After a thorough shrinking, cut the ends of the fabric
along drawn threads, or tear them straight. Press,
shrinking the torn ends if required.
Cut into two pieces along the true bias.
If you have a padded table, one way to mark the true
bias is to measure one foot from one end on both selvages,
then start a fold at one of the marks and bring the other
mark down to touch the selvage. Press the bias crease in.
For an unpadded table: make marks and fold as above, then
mark the selvage again where the mark touches it. Unfold
and use a folding ruler or a chalk line to draw a line from
one mark to the other. A gridded cutting mat can be used to
mark the line, but mark it before you cut it; don't try to
cut along a line that hasn't been drawn yet.
Sew the two ends together and press the seam.
You now have a short, wide piece of bias tape.
Mark the tape for dividing into narrower pieces. One
way is to fold the tape in half, iron in a crease, open it,
fold each edge in to meet the crease, etc. This method
works best when there is a certain amount of tolerance in
the final width. Another is to mark all the cutting lines
with a very long ruler, carefully measuring the space
between them. Be careful to let the cloth lie flat and
relaxed so that it won't change dimensions while you are
working on it. A #2 pencil makes a fine, non-smudging line.
Graphite doesn't come out, but the edges will be covered.
Start cutting the tapes at each pointy end. You will
snip one selvage at the right end, and the other selvage at
the left end.
Sew the remaining selvages together, being careful to
match each cutting line to its continuation at the seam
line, not at the edge. Press the seam, which will spiral
around the tube you have created. Because the cutting lines
were offset, they will be joined end-to-end into one cutting
line which spirals around the tube.
Stick a piece of plywood (or anything flat, hard, and
smooth) inside the tube, and use a ruler and pencil to true
the cutting lines where they cross the new seam. Any jog
that is visible at all is likely to make your hand waver
when you are cutting.
Cut along the cutting line with scissors.
If you use a knife and cutting mat -- and if this is
*not* your first venture into tape-making -- cut the middles
of the cutting lines before sewing the seam, while you can
still spread the tape out flat. Leave an inch or two uncut
at each end. After pressing the seam, finish the cuts with
scissors, or put a small mat inside the tube.
Generic instructions for cutting tape,
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when seams are not a problem:
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By some means or another, produce a short, wide piece of
tape and proceed from that point in the above instructions.
From ample yard goods:
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Cut a triangle off each end of a length and make the
scraps into scarves, or triangular bandages for your first-
aid class. If the cloth is only 39" wide and standard 40"
bandages are wanted, mark the selvages one inch from each
end, and draw the bias lines starting from these marks. Cut
one-half inch off the sharp point of the scarf, and fold
under a quarter inch. When the raw edges are hemmed, it
will look as though you had cut a forty-inch square in half,
and mitered the hems at the points.
From scraps:
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Study the shapes of the pieces. There might be a
reasonably large piece that can be trimmed into a diamond
shape. There might be two pieces to trim into trapezoids
and seam together. You might sew a triangle to each end of
a rectangle, or a triangle to one end of a trapezoid, or sew
two triangles to each other.
To make tape when seams are a problem:
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Straighten the edges of the piece for convenience in
marking. Each edge should be on the straight grain, the
cross grain, or the true bias, but shape is not a
consideration. Mark true-bias lines across the piece at
suitable intervals. Use a marker that won't fade. Each
time you need a piece of tape, find one that is about the
right length, and cut it off.
Pressing Bias tape:
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Some procedures call for tape that's entirely flat, some
call for tape that's pressed under on one edge, and for some
you'll want to press like commercial "single fold" or
"double fold" tape.
Single-fold tape has a quarter inch of each edge pressed
toward the middle. (This is why bias is rarely cut less
than an inch wide.)
Double-fold tape is pressed in half lengthwise after the
edges are pressed under. In commercial tape, the second
fold is a tad off-center, so that one side is a trifle wider
than the other. This way you can slip an edge between the
two layers, edge-stitch on the narrower side, and be sure of
catching the edge that's underneath.
After pressing the tape, it should be wound firmly on a
reel or card to prevent the folds from coming undone.
Cotton tape is more inclined to stay pressed if you starch
it heavily before you cut it into strips.
If you make miles of tape, buy a little tool that folds
it for you. Pressing single-fold tape with the raw edges
next to the board helps keep the folds folded until you
press them. Keep the nose of the steam iron right up
against the nose of the folder, so that the tape has no
space to unfold in. Guide the tape with the spare fingers
of the hand pulling the folder, to keep it centered; the
folder will quite cheerfully fold one seam allowance wider
than the other if left unsupervised. Guiding the fabric
also causes a slight drag, and the resulting hint of tension
makes the tape want to fold.
It is also possible to push the gadget along the tape
with the iron, but I've forgotten the details. I think I
did it raw edges up, and with the iron sideways to prevent
the nose from pushing the folds outward.
Pulling the tape under a pin stuck into the ironing-
board cover isn't as convenient as using a gadget, but the
free middle of the pin can be any length that you have in
mind. Pull the tape through with the raw edges up, so that
you can encourage them as they approach the pin.
If you are making only a yard or two, take advantage of
the natural tendency of bias to fold exactly in half. Fold
the tape in half lengthwise and iron the crease. Iron it
open -- hastily and without steam -- and fold first one edge
and then the other to meet the crease-mark down the middle.
Single-fold tape is finished; make double-fold tape by re-
pressing along the first crease.
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Department of "well, duh!"
10 July 2007: I just read
I have read a tutorial saying that the way to make bias tape is to fold the fabric along the bias, pin that fold in, then mark cutting lines parallel to the fold and cut strips with a rotary cutter (thus cutting two layers at once), working from the outside toward the fold. Which was illustrated by a picture of a cutter near the line nearest the fold -- the pictures in that series of tutorials are often uninformative or inept. The purpose of working toward the fold, of course, is to preserve the fold to keep the two layers lined up. If you try this, I'd suggest pressing the fold in instead of pinning it. It makes the fold more definite and easier to measure from, and the pins would get in the way of laying the ruler to mark the first line. I'd also suggest cutting a strip of cardboard to the exact width of the desired tape and using that to draw the lines. But when I draw parallel lines, I measure at right angles to the guide line and make dots that I later connect. That way all the lines are measured directly from the guide line. ------------------------------------------------------------ I don't think I've mentioned anywhere how useful a "laser level" is for marking bias lines. Tools, PAGESEW\RUFFTEXT\ROUGH007.TXT, explains how to use it. I mark only a few lines, and then measure from those when I'm cutting my bias-cut bras. The scraps usually afford an ample supply of long pieces of bias tape for binding the armholes, but sometimes I'll mark off several pieces of tape before laying out. ------------------------------------------------------------ EOF