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Sewing Machines

There is a huge range of sewing machines available today, ranging from basic models that do straight and zigzag stitch, to computerized embroidery machines that can stitch beautiful embroidery designs that you have customized yourself.

A sewing machine helps you to stitch faster, creating neat, even stitching time after time. Using the correct feet also helps with different types of sewing, whether it is inserting a zipper or creating perfectly formed buttonholes every time. Using different stitches that are built into the sewing machine enables you to embellish and customize by adding decorative stitching, trims, and fringe.

HOW THEY WORK

Electronic models stitch automatically when pressure is applied to the foot pedal – the heavier the pressure, the faster the machine stitches. Stitch choice, length, and width are chosen by changing the direction of dials or buttons, usually located on the front of the machine. They might also have a small LCD screen to show selections made.

Computerized models are fully automated – they automatically set the correct stitch tension, length, and width for the stitch you have chosen on the LCD touch screen. The screen also displays the recommended foot, and the option to change the stitch length or width, etc., to suit your own preferences. For instance, you may select a straight stitch, but want to increase the stitch length to maximum in order to make a gathering stitch. The automatic tension means that you can sew a single layer of flimsy fabric as evenly as multi-layers of denim or fleece. Computerized models also have a variety of embroidery designs and alphabets built in.

Stitch dials

An LCD display

CHOOSING A NEW SEWING MACHINE

Which type of sewing machine you buy will depend on budget, type of sewing, and personal preference. However, always buy the best you can afford, even if it has more features than you need at the moment– you can grow in to them. The following are a few basic guidelines to consider when choosing a new machine:

• Try out different models in your budget range to see how they sew different weights and types of fabric. Take your own fabric samples to try.

• Check the ease of threading both top thread and bobbin. Can the bobbin be wound with thread without unthreading the top thread and needle? Useful if a new bobbin is needed in the middle of a seam! Drop-in bobbins are less awkward than front-loading (or rotary hook) bobbins.

• Most modern machines have snap-on feet, which makes changing feet for different sewing techniques much easier. Check what feet are included in the basic price and what optional extras are available. Essentials are straight stitch, buttonhole, zipper, blind-hem, darning/free motion, appliqué.

• Look for a variable stitch speed which allows you to control how fast or slow you stitch. This is very important when stitching around tricky curves and corners or applying appliqué.

• If you intend to sew soft furnishings and other large projects, check the size of the throat space between the body of the machine and the needle. Bigger is better in order to fit large quantities of fabric through. Equally, a wide flatbed surface helps guide fabric. Some machines have an optional extension table.

• If you intend to carry your machine to workshops, check the weight and portability. What type of cover does it have? Note that computerized machines are much heavier than electronic machines.

• Ask about warranty, servicing, and repair facilities. Many manufacturers offer a 3- to 5-year warranty.

• Ask about courses, workshops, and after-sales service. Many manufacturers offer tutorials as part of the purchase price.

• How easy will it be to update a computerized model? Technology continues to advance, bringing new developments and stitch choices– can your preferred model be updated?

THREADING

Each sewing machine looks slightly different depending on the model and manufacturer. However, the main principles are the same on all. Check your user’s manual to determine where the relevant features are on your model.

Upper thread

Most machines have one or two upper-thread pins on which the thread spool is placed; these may be vertical or horizontal. Which way round to place the spool (with thread coming over the top or from under the spool) is important because it can affect the way the machine stitches, so check your user’s manual. Once the thread is on the pin, add a spool holder to keep the spool from bouncing up and down the pin when it revolves (which will cause uneven stitching or broken threads). The thread is then taken from the spool, through a thread guide on the top of the machine, down, then up through tension disks before being fed behind a hook on the needle column and then threaded from the front to the back of the needle (diagram 1).

Diagram 1: Upper thread

Bobbins

Although you can buy universal bobbins, it is preferable to use those that are supplied with the machine because some models get temperamental if using other types of bobbin. Bobbins can be wound with the same thread as the upper thread or with a special bobbin fill if doing machine embroidery or lots of appliqué (bobbin fill is finer, making it ideal for heavily concentrated stitch areas). Place the bobbin on the bobbin winder pin (at the front or the side of the machine) and push the pin into the wind position. On modern machines this disengages the needle and allows you to wind bobbins without unthreading the upper thread (check your user’s manual). Use the bobbin winder for general sewing thread to ensure an evenly wound bobbin. If it is too loosely wound or uneven, it may cause the bobbin to jam when sewing, which can cause broken or uneven stitching. (If you are using speciality threads for a decorative finish, hand-wind them onto the bobbin and then stitch slowly.) Clean the bobbin area frequently using the brush provided in the tool kit to prevent fluff build up (which can jam the machine).

Winding a bobbin

STARTING TO STITCH

It is preferable to bring up the bobbin thread before you start to stitch to prevent the threads tangling at the start of a seam. To raise the bobbin thread, turn the fly wheel by hand to lower and raise the needle. As the upper thread comes back up, pull it from behind the needle to bring up the bobbin thread loop and then pull both together to create a 2–3 in (5–8 cm) thread tail.

Stitch length

An average stitch length for medium-weight fabric is 2.5–3 mm or 10–12 spi (stitches per inch). Stitch length is altered by a dial on electronic machines, or by tapping the increase/decrease points on the LCD screen of a computerized model. There will be a minimum and maximum stitch length – minimum is used to stitch on the spot and maximum for basting or gathering stitches. Shorter stitch lengths are used for finer fabrics, and longer stitch lengths are used for sewing bulkier fabrics.

Stitch width

The stitch width is only applicable on stitches that have a sideways element, such as a zigzag stitch or decorative stitches. Adjust with the dial or LCD screen as for length, reducing or increasing to suit the fabric weight and stitch choice.

HELPFUL HINT:

Test stitch the length and width on a sample made up of the same number of layers and interfacings, etc. Adjust the length/width as necessary to achieve an even, straight row of stitching.

To ensure the fabric is not pulled down into the throat plate and to prevent threads tangling at the start of stitching, hold the thread tails at the back when making the first few stitches.

Stitch tension is correct when the upper thread shows on the top of the fabric and the bobbin thread shows on the underside. The two threads are interlocked between the fabric layers.

GUIDE TO OTHER MACHINE PARTS

Flywheel – Also known as the hand wheel. Turn it to lower and raise the needle, step by step.

Needle – Sewing machine needles have a flat surface on one side of the shaft. For most machines, this is placed in the needle column facing to the back. To secure the needle in position, tighten the screw with the screwdriver provided in the tool kit.

Presser foot – This is used to help keep the fabric in position as it is fed through when being stitched. Snap-on feet are easy to remove and replace. The presser foot is lifted or lowered using a lever on the side or back of the foot column or by a computerized button.

Feed dogs – Positioned under the presser foot, these raised, jagged edges move back and forth when the machine is in use in order to feed the fabric as it is being stitched. Lowering the feed dogs disengages them and thus enables you to move the fabric in any direction as it is being stitched.

Throat plate (or needle plate) – This metal plate has a central hole which fits over the feed dogs and provides a space for the needle to go down and pick up the bobbin thread. The different markings are used as a guide for seam width. Alternative throat plates with smaller apertures are available for some models.

Flat bed and free arm – These are the terms for the sewing surface. The flat bed usually incorporates the tool kit/machine accessory case which can be removed to make the sewing surface. The free arm is a thinner base used when sewing small items, such as cuffs or trouser hems.

Presser feet

Every sewing machine is provided with a basic range of feet which help sew specific techniques, such as a general purpose foot, zipper foot, and buttonhole foot. Other feet are usually available as optional extras. Each has different widths, grooves underneath to move smoothly over concentrated stitch areas, or hooks and angles through which trims, piping, etc., can be fed.

All-purpose foot – The most frequently used foot, ideal for straight stitching.

Zipper foot – These can vary in appearance, but all are designed to allow stitching close to the zipper teeth.

Buttonhole foot – These vary from model to model. Some have a slot to insert a button at the back. The underside has deep grooves to allow it to glide over dense stitching.

Embroidery/appliqué/satin stitch foot – Usually clear plastic, a wide groove on the underside helps the foot glide over concentrated stitching.

Blind hem foot – Used to machine stitch blind hems, the foot has a metal guide against which the folded fabric is fed.

Overcasting foot – Designed to stitch at the edge of the fabric, it has a wire brush on the underside to prevent the fabric edge from rolling or puckering.

Walking foot – Although large and cumbersome to look at, this foot helps feed fabric layers through evenly and is ideal for fabrics with a pile such as fur, or for accurately matching plaids and quilting several layers.

All-purpose and zipper feet

Walking foot

Embroidery foot, blind hem foot and overcasting foot

Buttonhole feet