What is the difference between 4 thread vs 5 thread overlocker?

Which overlocker should I buy 4 thread or 5 thread? Which one to choose? an overlocker with 4 threads or one that can sew with 5 threads. What is the difference between them?

Yes, the 5 thread overlocker can be more expensive, but, is it worth choosing over the cheaper 4 thread models. Many yours ago, only industrial overlockers in factories used 5 threads. Today, we can buy a advanced 5 thread overlock sewing machine for home use, and it is the same foot-print size, as a 4 thread model. 

Using an overlocker, you can sew a host of various stitches, rolled hems, narrow hem stitch, mock flatlock, blind hems, pipcot edging, or regular serging of the raw material edges to stop fraying. They are the perfect tool to add a professional finish to garments, they are not only useful, in fact, having one is a necessity when your project uses knit stretch fabrics.

Let's delve into the differences:

4-Thread Overlockers

Features:

• Stitch Types: Typically includes 3-thread overlock, 4-thread overlock, and rolled hem stitches.
• Seam Types: The 4-thread overlock stitch is strong and flexible, making it suitable for seams on knit and woven fabrics.
• Common Uses: Ideal for finishing edges, sewing seams, and working with a variety of fabrics, especially knits. 

4-Thread Stitches Overview:

Using 4 threads, can cover a wide selection of edging stitches, flatlock, rolled and narrow hemming. 

Advantages:

• Can handle most general sewing and serging tasks.
• Generally easier to thread and use compared to a 5-thread overlocker.
• Usually more affordable than a 5-thread overlocker.
• 4-thread overlockers are typically easier to thread and operate, making them a better choice for beginners and intermediate sewers.
• 4-threaders are generally less expensive, making them a good choice for hobbyists and those on a budget.
• If you mainly sew standard garments, knitwear, and everyday sewing projects, a 4-thread overlocker is usually sufficient. 

Suitable for users:

• Home sewers and hobbyists who primarily work with standard garment construction.
• Those who want a reliable and versatile machine for general sewing projects.

5-Thread Overlockers

Features:

• Includes all the stitches of a 4-thread overlocker plus the 5-thread safety stitch and most can also sew a chainstitch.
• The 5-thread safety stitch combines a 2-thread chain stitch with a 3-thread overlock stitch, providing a strong, durable seam, giving two rows of straight stitching for a stronger seam.
• It can sew an overlock edging stitch using 2-threads and at the same time sew a 2 thread straight chain stitch.
• The chain stitch component is useful for additional durability and stability, especially in high-stress areas of garments. It uses one or sometimes two threads in conjunction with the looper to form, what loos like a straight stitch. You can read more detailed information about a chainstich here.

5-Thread Stitches Overview:

You can view the additional stitches available on an overlocker that uses 5 threads. Note the much sort after 5 thread safety stitches and chainstitch, as used by professional seamstresses and tailors.

Advantages:

• Strength: The 5-thread safety stitch is extremely strong and durable, ideal for heavy-duty sewing. 
• Professional Finish: Often used in industrial and professional garment production for its robust seams. 
• Flexibility: Offers more stitch options and the ability to combine overlock and chain stitches. 
• Some models that use 5-threads, can also sew an additional stitch called a cover hem or cover stitch. What is a cover stitch?
• If you work with mostly stretch fabrics or need exceptionally strong seams, or if you are involved in semi-professional sewing, a 5-thread overlocker may be more appropriate.
• The extra functionality and stitch options can be worth the investment for more serious sewers. 

Disadvantages:

• 5-thread overlockers are more complex and may require a higher skill level to utilize fully.
• Often more expensive.

Suited for users:

• Advanced sewers and professionals who need extra strength and durability in their seams.
• Those who sew heavy fabrics or high-stress garments, such as outerwear, workwear, and sportswear.
• Sewers looking for a machine with more versatility and stitch options.

Let's check an alternative:

If you intend to venture into the realms of a 5-thread overlocking! It can open up other options; for example a coverlock machine which also uses 5 threads, it is dual-purpose machine comprising an overlocker with a cover stitch machine combined. It can sew a professional cover stitch.  The image below show some cover hems sewn on a 5 thread coverlock machine.