Overlock vs Lockstitch Sewing Machines

If you’re setting up a tailoring shop or a small garment unit, one of the biggest confusions you’ll face is choosing between Overlock and Lockstitch sewing machines. Both are essential in the garment industry, but they serve very different purposes.

While lockstitch machines create strong, straight seams for general stitching, overlock machines handle the finishing touches — trimming fabric edges and preventing fraying. To build an efficient setup, it’s important to understand what each machine does, how they differ, and which one best fits your stitching needs.

Let’s dive into the Overlock vs Lockstitch comparison and make it simple for you to decide.

1. What Is a Lockstitch Machine?

A lockstitch machine is the most common type of sewing machine used worldwide. It uses two threads — one from the needle and one from the bobbin — that “lock” together in the middle of the fabric to form a strong, durable stitch.

These machines are ideal for:

Straight stitching
Joining fabric panels
Topstitching and hemming
General garment construction

Examples include models like Jack F5, Usha S2 Direct Drive, or Singer Merritt Tailor, which are built for precise, professional stitching.

Key Features:

Uses two threads (needle + bobbin).
Produces a straight, neat stitch.
Suitable for most types of fabrics.
Commonly used in tailoring shops and factories.

2. What Is an Overlock Machine?

An overlock machine, also known as a serger, is designed for edge finishing. It trims the fabric edge and simultaneously wraps it with thread loops to prevent fraying. Overlockers can use 3, 4, or 5 threads, depending on the model, and they produce the stretchy, finished seams often seen inside T-shirts or knitwear.

These machines are perfect for:

Edge finishing and seam sealing
Knitwear and stretchy fabrics
Professional garment finishing
Decorative edging on dresses or home textiles

Brands like Jack, Revo, and Brother make reliable overlock models that combine speed with fine finishing.

Key Features:

Uses 3–5 threads.
Cuts and stitches simultaneously.
Prevents fraying and gives a clean finish.
Ideal for woven and stretch fabrics.

3. Structural Difference – How They Stitch

Feature	Lockstitch Machine	Overlock Machine
Thread System	2 threads (needle & bobbin)	3–5 threads (loopers & needles)
Stitch Type	Straight stitch	Overcast stitch
Fabric Edge Trimming	No	Yes, built-in knife trims edges
Elasticity	Less stretch	More stretch (good for knits)
Application	Construction stitching	Edge finishing

In short:

Lockstitch = Strength + Durability
Overlock = Finishing + Flexibility

4. Performance & Speed

In industrial setups, speed and accuracy matter most.

Lockstitch machines like the Jack F5 or Usha S2 can deliver up to 5000 stitches per minute, making them ideal for high-volume production of shirts, pants, and uniforms.
Overlock machines, while slightly slower (3500–4500 SPM), handle edge trimming and seam sealing in one go, saving time during finishing.

So, while the lockstitch may seem faster, the overlock reduces additional finishing steps — balancing efficiency in a different way.

5. Fabric Compatibility

Fabric Type	Recommended Machine	Reason
Cotton, linen, polyester	Lockstitch	Clean, firm seams
Knitwear, jersey, stretch fabrics	Overlock	Stretchy, flexible seams
Denim, canvas	Lockstitch	Strong structural seams
Light silk or chiffon	Overlock (3-thread)	Prevents fraying on delicate edges

Verdict:
If you mainly work with woven fabrics, the lockstitch machine is your foundation. If your projects involve stretchy or delicate materials, an overlock machine becomes essential.

6. Stitch Appearance & Function

Lockstitch Output

Produces a tight, flat seam with identical appearance on both sides. Perfect for visible stitching like top hems, collars, and straight joins.

Overlock Output

Creates a looped edge seam that wraps around the fabric edge. The stitch looks different on front and back but gives a smooth, elastic finish.

Pro Tip:
Garment manufacturers often use both — lockstitch for main seams and overlock for finishing edges — for the best results.

7. Maintenance & Ease of Use

Lockstitch Machines: Easier to thread and maintain; ideal for beginners and general tailoring.
Overlock Machines: Slightly complex threading (especially 4 or 5-thread versions) but deliver professional finishing once mastered.

Both require oiling, cleaning lint, and adjusting tension occasionally — but modern models like Jack F4/F5 (lockstitch) and Jack E4 (overlock) are designed with self-lubrication and LED work lights for convenience.

8. Pricing Comparison

Machine Type	Price Range (Ex-GST)	Typical Use
Lockstitch	₹18,000 – ₹25,000	Garment assembly, straight stitching
Overlock	₹22,000 – ₹30,000	Edge finishing, knitwear production

Though slightly more expensive, overlock machines save time during finishing — which can translate into higher productivity and profit for professional tailors.

9. Which One Should You Choose?

Your choice depends on your type of work:

User Type	Recommended Machine	Reason
Boutique Tailor	Lockstitch + Overlock	Both essential for quality finishing
Garment Factory	Overlock + Lockstitch	Combination ensures fast production
Home Tailor	Lockstitch	Affordable and easy to use
Knitwear Designer	Overlock	Handles stretch fabrics perfectly
Alteration Shop	Lockstitch	Works for hemming and repairs

For most professional setups, having one of each is the ideal combination — the lockstitch builds the garment, and the overlock refines it.

10. Final Verdict

Both lockstitch and overlock sewing machines are crucial in tailoring and garment manufacturing. They don’t compete — they complement each other.

Choose Lockstitch for durable seams, topstitching, and structure.
Choose Overlock for finishing edges, preventing fraying, and stretchable seams.

If you’re setting up a new tailoring unit or upgrading your equipment, consider starting with a lockstitch machine like the Jack F5 or Usha S2, and then add an overlock machine like Jack E4 or Revo 747 for finishing.