Ten Shortcuts to Successful Bag-Making
By Nicole Mallalieu
These Tips may seem like the “long way around”, but
ignoring these vital steps actually creates a lot more work…
or a badly-finished bag!
1. It’s worth buying good bag patterns (…unless
you know how to make very accurate bag patterns).
WHY?
Patterns are made to fit together as a bag should - the seams all
match, the lining is the correct depth for the bag, and all the
details are marked where they need to be on the bag. Without an
accurate pattern, the pieces may not come together as they ought,
and because bags are quite small objects, these kinds of pattern
mismatches stand out alarmingly. Often the only option is to unpick
and recut the offending piece, or the whole bag.
Using a pattern reduces the likelihood of having to unpick, re-cut
or disguise mistakes, and you can make the same bag over and over
and know that it’s going to work every time. If you start
with a paper pattern, you also have a clear point of reference to
work from if you want to tweak the design slightly.
2. Take care to identify each pattern piece.
a) If you draft your own patterns, or copy them from a book, it’s
worth taking the time to carefully label each pattern piece with
grain lines, notches, identification labels and cutting instructions
b) Before you begin laying out your pattern for cutting, make sure
you know what each piece is, and which fabric you will be cutting
with it.
c) Separate the pattern pieces into groups according to the fabrics
they will be used on.
d) As you lay out the patterns on each piece of fabric, make sure
you know which way each piece will sit on the finished bag, and
cut them according to the correct fabric direction or print placement.
e) Make sure that the grainline is running parallel to the selvage
edge of the fabric.
WHY?
Read the pattern pieces carefully! Unlike most garment patterns,
which have obvious body shapes to tell you what they are, bag pattern
pieces are often not easily identifiable. They are usually abstract
or geometric shapes, and it’s easy to mistake one piece for
another.
It’s also important that you recognise which is top and which
is the bottom of a pattern piece. Apart from reducing confusion
when you’re actually sewing the bag, you have to be aware
of directional patterns and naps in the fabric. You may have to
think about matching stripes or carefully placing a print detail.
Cutting a bag piece on the right grain is important. The strength
of a bag often relies the strength of the straight grain, and stripes,
prints and decorative weaves all need to be cut following a consistent
grain.
You can waste a lot of time and fabric by cutting the wrong piece
in the wrong fabric, or in the wrong direction. Taking the time
to make a few checks beforehand may save you hours of unpicking
and re-cutting.
3. Use Fabric Efficiently
Before pinning out a pattern, get all the pieces for that fabric
and move them into the most efficient arrangement (or “lay
plan”) that you can. Try a few different lay plans if necessary,
and see which one uses the shortest length of fabric (and creates
the least amount of unusable scrap).
When you cut fabric on the fold, start arranging your pattern pieces
from the outside (selvage) edge first. Any leftover fabric will
be on the folded edge, and therefore twice the width than if it
was cut on the selvage, and much more usable for another project.
WHY?
It’s good practice not to waste fabric. You never know when
you might have to re-cut a piece, and you never know how much you’ll
need for your next project. Aim to have as much left over as you
can to cover all possibilities.
4. Cut out the pattern accurately. Use pins and sharp scissors
when you cut out bag pieces. Aim to cut as close to, if not ON,
the cutting line of the pattern.
WHY?
Once the pattern is cut out and taken off the fabric, you no longer
have a line to show you where to sew. You have to gauge where to
put the seam by knowing the seam allowance depth from the outside
edge of the fabric. If the outside edge has moved a few millimetres
out, though bad cutting, then the gauge for your stitch line is
out.
Even on a simple two-piece bag, if you’re a few millimetres
out on each cutting line it can add up to be as much as a centimetre
out around the top of a bag. On a bag with more seams, the margin
for error increases. It can be too big to fit to the facing or lining,
and this leads to puckering, stretching, unpicking and/or re-cutting
pattern pieces.
You can spend much more time unpicking and re-doing than the time
it takes to pin and cut the pieces carefully.
5. Follow the pattern instructions for cutting notches and
marking dots on your fabric.
WHY?
Because the individual pieces of bags are often geometric or abstract
shapes, it’s not easy to tell which way is the top and which
is bottom, and where bag pieces join others. Once you’ve cut
and unpinned your pattern, notches, nicks and dots are the only
guidelines for identification, alignment and the placement of pockets
or details. Without them your bag can end up being quite misshapen.
6. Sew at the correct seam allowance depth.
a) If there are notches on the pattern to mark the depth of the
seam allowance, mark them onto the pattern piece as you cut it out,
and USE THEM (!!!) as a guide to where to start each seam.
b) At the beginning of a seam, put the needle through the fabric
at the correct seam allowance, and line up the edge of the fabric
with a fixed point on the sewing machine – whether that’s
a seam guide (one of the lines on the machine bed) or the edge of
the presser foot. Keep your eye on this fixed point, and keep the
cut edge of the fabric travelling evenly along it as you sew the
seam.
WHY?
One of the most common reasons for bag pieces not fitting together
is that the seams are sewn in the wrong place (ie. at the wrong
seam-allowance depth).
The matching seamlines of a bag pattern are designed to be exactly
the same length, to make the pieces of the bag all fit together
smoothly. If you sew with the wrong seam allowance – or an
inconsistent, uneven seam allowance – you are often trying
to sew the fabrics along completely different lengths. This can
mean that the bag pieces themselves will appear “too short”
or “too long”. It may create a “twist” in
the bag, as front and back no longer sit square.
Because bag patterns have lots of seams that transect other seams,
it’s important that all the pieces are sewn accurately if
they are to fit. For example, facings and linings each have to be
sewn with exactly the same seam allowances as the outside of the
bag, otherwise they will be too large or small to fit to the bag
around the top seam. Fabric may have to be stretched or puckered
to sew the pieces together.
Sewing with inconsistent or uneven seam allowances can create results
similar to inaccurate cutting. If you have a combination of inaccurate
cutting and inaccurate seam allowances, it can be disastrous.
7. DON’T trim off “leftover bits” when seams don’t
fit together.
If a bag piece appears to be a different length than the piece to
which it is seamed –
a) Check the seam allowances to make sure they are accurate.
b) Check the notches to make sure they match.
c) Check that the fabric piece is the same size as the paper pattern
piece.
d) Check that the seamlines on the patterns are the same length.
e) Unpick the pattern piece and correct the problem.
WHY?
If you have “leftover bits” of fabric at the end of
a seam, it usually means that your cutting or your seam allowances
are inaccurate. Occasionally it may mean that the pattern is inaccurate
(see TIP No. 1). It can also happen when notch points and pins are
not used, and one piece of fabric has stretched slightly with sewing.
By randomly trimming pieces off, you exacerbate the problem by
changing the shape of the bag piece. Other pieces of the bag may
then not fit to it. If it comes together at all, the bag will end
up being misshapen, and there’s a good chance the lining wont
fit.
8. Always secure the ends of each seam with “back-tacking”
or “back-stitching” (a few reverse stitches) to stop
it unravelling. Don’t simply tie the ends of the threads together.
WHY?
Making a bag involves a lot of fabric manipulation and seam-allowance
clipping. As you fit together lots of small pieces, and turn them
all through to the right side (through a small gap in the lining),
stress on the seams can be cause the ends to pull apart if they
are not locked together securely.
If they are not secured properly, the seams may even split AFTER
the joined pieces have been attached to another piece by a transecting
seam (for example, the side seam may split at the point where it
meets the facing or lining). It takes longer to unpick the transecting
seam and sew the side seam again than it does to secure the ends
of the side seam in the first place.
9. At the end of each seam, clip away the corners of the
seam allowances.
Start about 3cm (1 ¼ “) from the end of the seam,
and clip towards the end of the seam. Don’t cut the stitches
– clip towards a point about 1-2mm away from the last stich
of the seam.
WHY?
Bags have a lot of seams converging at particular points. If the
seam allowances are left whole they add bulk to these points, and
can make it difficult (or impossible) to sew through all the seams.
The bulk of the seam allowances may also be seen from the outside
of the bag as an ugly bulge.
By clipping the seam at the angle described above, you will reduce
bulk in the seam allowance, while leaving enough fabric to effectively
press the seam allowance open (see below).
10. Press each seam allowance open as you sew the bag together.
Don’t leave all of the pressing until the bag is finished.
WHY?
Pressing the seams open creates clean, smooth lines on the bag,
and it makes shapes easier to turn through to the right side. It
makes smooth surfaces for topstitching. Good pressing can be the
difference between a bag that looks amateurish and one that looks
well finished.
As the bag comes together, you are creating an increasingly enclosed
shape, and it becomes increasingly difficult to access all the seams
with the iron. By pressing as you work, it’s easier to completely
flatten all the seams properly, and reduces the time spent on a
“final press” when the bag is finished.
Copyright Nicole Mallalieu 2006
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