Overlock vs Lockstitch: What's the Difference?
A clear explanation of how overlock and lockstitch machines differ, and why most production lines need both.
The two machines work together on nearly every garment line, but they do different jobs.
The lockstitch machine
A lockstitch machine makes the strong, flat seam that joins fabric pieces. It uses two threads (needle and bobbin) locked together, and is used for almost all main seaming.
The overlock machine
An overlock machine trims and overcasts the fabric edge in one pass, stopping it from fraying. It uses three to five threads and is essential for knitwear and edge finishing.
Why you need both
A lockstitch cannot finish edges; an overlock cannot comfortably make the flat main seams. A garment line uses lockstitch for construction and overlock for finishing. For a standard set-up, pair the 6150D lockstitch with the 747D overlock.