overlock sewing

7/27/2019 Overlock sewing

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Everything you need to know

about

OVERLOCKING

This booklet

has been designed to enable you to keep a

record of the different types of stitching (basic,

special or decorative) that you will achieve if youfollow the lessons in our DVD Everything you

need to know about overlocking.

The physical record of each stitch type will be a

reminder when you come to use your overlocker

for future projects. The data you record here will

specically relate to your own machine.

Our students usually purchase a folder with clear

plastic pockets to place their page and samples

into.

Getting started

Sample Fabrics

To follow the basic lessons we suggest youprepare samples of calico cut to t the booklet

pages. Most samples will require two layers.

You will also need knitted fabric or lycra, super

stretchy fabric, ne fabrics and rm fabric -

enough of each of these to create samples.

Threads

For the purposes of practicing, we suggest you

use the colour threads that your machine is colour

coded for, so that you can easily see on yoursamples how each needle or looper thread is

working. It will be easier to make tension or other

adjustments accordingly.

We wish you all the best as you learn from these

lessons. We hope you will become much more

condent with the use of your machine.

From the team at Sewing With Condence.

LESSON BOOKLETOverlockers, also known as Sergers, can simplify and speed up so many of the common tasks used in

sewing. Working at more than twice the speed of a domestice sewing machine, an overlocker is a plea-

sure to use and makes the task of sewing much quicker, neatening edges as you sew.

2011 Sewing With Condence Ltd.


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Your Overlocker should have

A threading

diagram on the

machine indicating

the sequence and

colour coding for

each thread.

Each threads path

should be colour

coded on themachine, from the

thread stand to the

needle or looper.

A self-threading lower looper.

Clip-off presser feet that enable you to reach the

needles and loopers easily.

Tension which releases as soon as the presser foot

is lifted.

Start at the beginning

Choose a good quality thread.

For regular sewing with normal tension, use the

same type of thread for the loopers and the needles.

Try not to use one large cone for one looper and a

small 1000 m reel for the other looper as this could

result in uneven tension.

Do not use woolly thread referred to as flock or

floss in the needles, as this will keep on breaking,

jamming, perhaps even breaking the needles.

Thread one reel at a time, starting at the thread

stand and following the indicated path up to the

needle or looper. Always start with the upper looper then the lower

looper.

Note: Follow the threading sequence for your specificmodel.

Bring all threads under the presser foot to the back

and drop the presser foot.

If you have a problem it is always better to remove

the threads and start right from the beginning.

Pulling in a new thread.

You can knot and pull a new thread through by fol-

lowing these basic guidelines.

1. Cut the threads between the thread stand and

the thread spool.

2. Knot the new threads in position.

3. Remove the needle threads as the needles have

to be threaded last.

4. Put the tension levers to the lowest number and

lift the pressure foot to disengage the tension.

5. Pull one thread at a time to let it run through the

thread guides.

6. Check that each thread is threaded correctly.

7. Do a test after each thread change.

Threading is the first step in using an overlocker, but is the most important

step, as faulty threading will result in no stitches or faulty stitches forming.

Threading an overlocker might look challenging but a good quality overlocker,

will assist you by making this important step as easy and time saving as pos-sible.

Threading the Overlocker

Always start with the upper looper,

following the indicated path.


BASICLESSON

1


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Left Needle - Right Needle -

Upper Looper - Lower Looper -

Cutting Width - Stitch Length -

After you have completed your threading using the 4 different colour

threads, and the test is to your satisfaction note the settings below.

Threading your overlocker


BASICLESSON

1


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The 4 THREAD OVERLOCK STITCH can be used for

Sewing up highly stretchable fabrics, e.g. gym and swimwear where seams will be under high strain.

Special techniques, e.g. sewing on elastic, gathering with the overlocker, making piping and securing itin position.

Decorative stitching, e.g. when doing tucks.


4 thread overlock stitchTwo needles and two loopers are used. The 4-thread overlock will allow for fabric elasticity,

which makes it an ideal stitch to use on knitted fabric, e.g., track-suiting and T-shirts

Because the finished stitch width = 6mm, this stitch can be used to sew and overlock a

seam in one operation. For example, in making tracksuits it will be strong enough.

Preferably use calico for this test.

Cutting width test: Cut fabric 15cm long & 6cm wide. Divide in 3 equal segments = 3 cutting widths

Stitch length test: Cut fabric 16cm long & 6cm wide. Divide into 4 equal segments = 4 stitch lengths

4 thread

SL = 2.5 CW = 2

Varied Stitch Width

CW = 1, 2 & 3

Varied Stitch Length

SL = 1, 2, 3 & 4

BASICLESSON

2


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The 3 THREAD OVERLOCK STITCH can be used

To finish off frayed edges on woven fabrics or to form an open or closed single seam.

To sew and finish off a seam in one operation when sewing lightweight knitted fabric, such as T-shirting.

To sew decorative finishing, e.g. flat seams, decorative edges, tucks and making cords.

To sew roll hemming and its variations such as pintucks and lace insertions.


Left Needle-

Right Needle-

Upper Looper

Lower Looper

Cutting Width-

Stitch Length-

Left Needle-

Right Needle-

Upper Looper

Lower Looper

Cutting Width-

Stitch Length-

Left Needle-

Right Needle-

Upper Looper

Lower Looper

Cutting Width-

Stitch Length-

WIDE NARROW VERYNARROW

3 thread overlock stitchThe 3 THREAD OVERLOCK STITCH is formed by one needle thread, which anchors 2

looper threads.

The two looper threads meet on the edge of the fabric and the needle thread acts as a

straight stitch.

Record your machine settings below in each column for each sample you create.

BASICLESSON

3


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2 thread overlock stitchusing the UPPER LOOPER CONVERTER

Only one needle and one looper are used. The needle thread anchors the lower looper

thread, which rolls or loops over to the top of the fabric.

2 thread seam finishing 2 thread Roll Hem 2 thread Flatlocking

Fora2-threadoverlockstitch,usethe

upperlooperconverter.

Thestitchlookslikea3-threadstitch

fromthetop,buttheneedlethread

forms,anevenVonthebottom.

Testforthecorrectstitchsettingby

pullingthefabricforthestitchtolieflat.

The 2 THREAD OVERLOCK STITCH can be used for:

Finishing off raw edges on woven fabrics especially on very lightweight fabrics where a soft seamfinish is required and where a 3- thread overlock stitch will be too thick and bulky.

Decorative stitching such as flatlock seams, as it will pull open and lay flat

Roll hemming and its variations

BASICLESSON

4


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4 thread overlock stitchingusing DIFFERENTIAL FEED

All overlockers today offer this feature. It means that the feed mechanism is divided into two

parts, which can operate as one or as separate parts

It can be set as follows:

Normal setting (N) for regular sewing. The two parts work together and the fabric is fed through evenly.

Special setting (1.5 to 2) for knitted fabric. The front section of the feeding mechanism moves up to twice the

distance of the back section, resulting in the fabric being pushed together and thus preventing it from stretching

during sewing.

Special setting (0.7) for thin and difficult to handle fabrics. The back section of the feeding mechanism moves

over a longer distance than the front section, resulting in the fabric being pulled through to the back, thus

preventing the fabric from puckering.

The differential feed feature will also enable you to gatherwith the overlocker and create a Super Stretch Stitch

which is a very elastic stitch formed using two needles and the lower looper. This stitch requires the Upper Looper

Converter and Woolly Nylon Thread (Also called floss or flock.)

Knitted fabric & lycra Thin Fabrics Gathering

Super Stretch Stitch

BASICLESSON

5


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Special hints when sewing rolled hems

When sewing a very fine and loosely woven fabric, use a

slightly wider cutting width to ensure a strong, neat edge

finish. Also start by cutting 4 cm off the seam allowance so

that the needle will enter the fabric with the first stitch,

Use a wide cutting width and tighter lower looper tension

when sewing stiff fabrics.

Avoid dog ears on corners: Start sewing, cutting 5 mm

deeper than the required amount and move towards the

cutting line. Sew up to 3 cm from the corner; sew at an

angle towards the corner to cut off 5 mm more than normal.

Roll hemmingThe new overlockers will sew roll hemming with great ease. No presser feet or stitching plates

need to be changed.

This stitch is ideally used as an edge finish on frills, sleeves and hems in fine fabrics.

On firm fabric On lightweight fabric On fine fabric

Set the overlocker as follows

Use a narrow three thread overlock or a

two-thread overlock stitch.

Set the cutting width to the lowest setting.

Set the stitch length to 1mm depending on

the thread and the required effect.

Set the tension dials as per your instruction

manual.

BASICLESSON

6


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Finishing Off ChainsBecause of the way an overlocker is designed, special techniques are required to use it

effectively, e.g. overlockers do not sew in reverse, so to finish off beginnings and endings of

seams the following techniques could be used.

SEAM BEGINNING

1. Sew a 3-4 cm thread chain.

2. Sew 2 stitches onto the fabric.

3. Lower needle into the fabric.

4. Raise the presser foot.

5. Straighten out the thread chain

and remove stitching from thestitch finger. Lay the threadsfrom the left back to the frontand lay it under the presserfoot.

6. Lower the presser foot.

7. Sew over the thread chain for2 cm and cut off the excesschain with the knife

SEAM ENDING

1. Sew to the end of the seam.

2. Raise the needle and presserfoot.

3. Remove the stitching gentlyfrom the stitch finger.

4. Turn the fabric over towards

you and lay it under thepresser foot so that the needleenters the fabric with the firststitch.

5. Lower the presser foot.

6. Sew carefully over theprevious stitching withoutcutting for about 2 cm.

7. Raise the tip of the foot and

turn the work away from you.

8. Stitch off the edge.

Sp

ecialTechn

iques

LESSON

1


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Sewing Outside Corners

1. Cut into the corners whereyou will be using thistechnique, cutting off theextra fabric you wouldnormally cut off with theblades - about 3-4 cm.

2. Sew up to the corner andone stitch over the edge ofthe fabric.


4. Pull the work slightly to theback to clear the stitch finger.

5. Turn the fabric and lay itunder the presser foot so thatthe cut edge of the fabric isagainst the knife.

6. Lower the presser foot and

needle.7. If necessary, pull all the

threads tight above the firstmachine guide. Continuesewing.

Sp

ecialTechn

iques

LESSON

2


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Sewing Inside Corners

1. Prepare your fabric with asquare shape cut out (as fora square neckline).

2. Snip into the corner up tothe stitching line. (You mayfind it easier to trim the seamallowance to between 3 -6mm depending on your StitchWidth).

3. Sew into the corner.

4. Straighten out the fabric.

5. Continue sewing

Cut

Cut out square

Sp

ecialTechn

iques

LESSON

3


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Sewing a Continuous Edge

1. As the blade of an overlockeris positioned in front of theneedle, special sewingtechniques are required.

2. Cut away a 4cm section outof the seam allowance.


4. Position the fabric under thepresser foot with the cut-away edge against the knife.

5. Lower the presser footand sew until the seam iscomplete.

6. Sew a few stitches over theprevious stitches withoutcutting them.

7. Raise the tip of the presserfoot.

8. Turn the work away and sewoff the edge.

Sp

ecialTechn

iques

LESSON

4


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Decorative Stitching

An overlocker can be used to its fullest

potential by using it for decorative effects.

It has become so easy to sew decorative

stitching.

With easy to set tensions and easy selections

of stitches e.g. roll hemming without the need to

change presser feet or stitch plates.

The possibility to convert a 3-thread stitch to a2-thread overlock stitch in seconds.

And the availability of specialized presser feet

and accessories, e.g. gathering, piping, cord

work, etc.

See the section on Overlocker Accessories

Some Tips for using Decorative Threads:

Decorative threads specially made for

overlockers are becoming widely available. You

may need to change the tensions when usingspecial threads on an overlocker:

When using slippery decorative thread use the

spool nets for even unwinding.

This is important only use decorative threads in

the loopers.

Threads must move easily and without

resistance through the thread guides and looper

eye and this should be taken into account when

purchasing the thread.

The thicker the thread, the looser the tensions.

To set the tension, set one tension at a time.

An important TIP sew slowly when using

decorative threads and pull the thread chain

gently backwards when starting to sew.

ALWAYS test-sew when using decorative

threads.

If you are not sure if you have enough

thread,you can calculate the amount of decorative thread

needed for your project as follows: Looper threads will

require 7 mt of thread for every 1 mt length of stitching.

So measure the length you need to sew and multiply itby 7.

Decorativ

e

LESSONS


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Decorative TucksDecorative tucks can be very effective, Turn and lock the upper blade away.

Fold the fabric and guide the fold on the guide mark on the presser foot.

TUCK VARIATIONS

1. Use a wide 3-thread overlockstitch with different threadcolours in the loopers.

2. Overlock parallel tucks.

3. Always start the tucks at thesame end and position thefabric so that when you sew

the pucks down you will getthe effect you are wanting.

4. Now sew the tucks downwith a sewing machine inalternative directions (See thelesson)

DECORATIVE EDGES

1. Use a 3 thread narrowoverlock stitch(See lesson3 of basic lessons). Usedecorative threads in theloopers.

2. Set the stitch length very short- to a satin stitch length.

3. The looper threads must meetat the edge of the fabric. (Thisis not a ROLL hemming stitch).

Decorativ

e

LESSON

1


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Decorative Roll HemmingApart from roll hemming being a practical stitch; it can be used very effectively as decorative

stitching.

(See Lesson 6 under the basic stitches section on how to set your machine for roll hemming).

Remember decorative thread is only used on the upper looper. When using decorative

thread your settings may need ro be adjusted.

Try these variations

Use a decorative thread in theupper looper.

1. Set the machine for a shortstitch length and sew a satin

stitch rolled edge.

2. NOW DO A TEST

3. You may need to adjust thetension to suit the thread

thickness.

Pin Tucks

This is very effective on shirts, skirts

& yokes.

Turn the blade away and sew the

rolled edge on folded fabric to form

a pin-tuck.

Lace Insertions

Place the wrong sides together

when you sew the lace in position

using a roll hem.

Decorativ

e

LESSON

2


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Flatlock SeamsFlat seams are formed by sewing a 2 or 3 thread overlock stitch to join two pieces of fabric

or on the fold of the fabric.

The fabric is then pulled open so that the stitch lies flat.

Settings for Flatlocking

1. Use a 3 or 2 thread overlockstitch. Set the needle tension at

the lowest setting, and the lower

looper tighter.

2. For a 2-thread overlock stitch,

use the upper looper converter.(See lesson 4 in basic lessons.)

3. The stitch looks like a 3-threadstitch from the top, but the needle

thread forms, an even V on

the bottom. These threads must

meet at the edge of the fabric

4. Test for the correct stitch settingby pulling the fabric for the stitch

to lie flat.

Decorativ

e

LESSON

3

overlock sewing

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