A sewing machine’s bobbin and hook interlock two threads inside the fabric layers, which is what makes a lockstitch strong, flat, and reversible. It’s a slower, more controlled process because you’re usually pivoting corners, backstitching, or matching pattern pieces not running flat-out. (The speed ranges above are typical figures published by manufacturers such as Brother and Janome across their domestic machine ranges, not measurements from independent testing.)

An overlocker’s loopers do something a sewing machine physically cannot they pass threads around the raw edge of the fabric rather than through the middle of it, encasing the cut edge as the blade trims it to a consistent width. 

The differential feed of two sets of feed dogs moving at slightly different speeds is the feature that makes this genuinely useful on knits. Turn it up to stop wavy seams on stretchy fabric turn it down to stop puckering on delicate or slippery fabric. Most home sewing machines don’t have this control at all.

Do You Need an Overlocker?

Not everyone does and that’s a genuinely useful thing to know before you spend the money.

You’ll probably benefit from an overlocker if:

• You sew garments regularly and want a professional, durable finish on the inside seams
• You work with knit or stretch fabric often (t-shirts, activewear, swimwear)
• You’re tired of the extra time zigzag-finishing every seam by hand
• You’re comfortable investing in a second machine and finding storage for it

You probably don’t need one yet if:

• You’re brand new to sewing and still learning your machine
• You mostly do patchwork, quilting, mending, or small craft projects
• Your projects are mainly wovens where a French seam or bias binding gives a perfectly good finish
• Budget or space is tight right now

This is where the two machines diverge most clearly. A standard sewing machine can sew knits using a walking foot, a stretch needle, and a stretch or narrow zigzag stitch but the seam has limited give, and it’s easy to end up with skipped stitches or a wavy seam if the fabric isn’t fed evenly.

An overlocker’s differential feed is specifically built to solve this. It gently stretches or eases the fabric as it feeds through, so the finished seam lies flat and moves with the garment instead of popping stitches the first time you sit down in it. That’s why most activewear, swimwear, and jersey-knit patterns are drafted assuming a serged or overlocked seam.

None of these give you the speed or stretch-friendly finish of a genuine overlocked seam, but they’re completely viable if you’re not ready to buy a second machine yet.

You’ll see combo machines advertised in Australia most commonly overlocker-and-coverstitch combination units. On paper, one machine that does both looks like the space- and money-saving option. In practice, most experienced sewists steer away from them: switching between overlock mode and coverstitch mode usually means re-threading and re-tensioning the machine, which eats up the time you were trying to save. 

If your budget allows, a dedicated overlocker plus a dedicated coverstitch machine (or simply a sewing machine with a stretch/coverstitch-style stitch) tends to be less frustrating long-term than one machine trying to do both jobs.

Buying Guide: What to Look For and What It Costs in Australia

Prices below are approximate AUD ranges based on current Australian retailer listings as of publication; always check GST-inclusive pricing and delivery costs at checkout, as these vary between retailers.

A few things worth knowing before you buy:

• A cheap overlocker can cost you more in frustration than it saves in dollars. Very basic models are often harder to thread, harder to tension correctly, and struggle with heavier fabrics.
• Look for a differential feed knob on any overlocker you’re considering it’s a genuine must-have, not a nice-to-have, if you plan to sew knits.
• Buying from an Australian dealer (rather than a grey-import) usually means local servicing, spare parts, and a warranty that’s enforceable under the Australian Consumer Law’s consumer guarantees worth factoring in even if the sticker price is a little higher.
• Reputable Australian retailers and dealer networks to shortlist from include Spotlight, Lincraft, and authorised Janome, Brother, Husqvarna Viking, Bernina, Pfaff, and Juki dealers.

Both machines are more sensitive to Australia’s climate swings than most people expect. In humid coastal and tropical areas (think Queensland, northern NSW, or the Top End), metal internal parts especially an overlocker’s blade and loopers can develop surface rust surprisingly quickly if the machine sits uncovered between uses. 

A fitted dust cover, a light coat of sewing machine oil on exposed metal before storage, and keeping the machine off the floor (away from damp) all help. In drier inland or southern regions, the bigger risk is dust and temperature swings in an uninsulated garage or shed, which can affect belt tension and electronics on computerised models over time. 

If you’re storing either machine for an extended period over a Christmas break, say a silica gel sachet inside the dust cover and a room-temperature spot indoors will do more for its lifespan than any feature on the machine itself.