Here are some of my ‘oh at last I understand that’ moments.

If you can, find an on-line manual for any serger/overlocker model you’re thinking of buying, and look at how the loopers are threaded. Some models have many aids to looper threading, others don’t !

Here is a tutorial on the types of stitches, from Threads magazine.

Which thread does what ?

This image (from that post) shows the 4-thread stitch.
Used for seams on knits, seam finishes on wovens.

This is the 3-thread stitch, using one needle thread and both loopers.
Left needle for a wider stitch, right needle for a narrower stitch.
Used for seam finishing.
3 thread stitch

Many other stitches explained in the above Threads post.

yellow – left needle
green – right needle
blue – upper looper
purple – lower looper
[these are just the colours in these diagrams, there is no standard use of colours, the colours may be different on your machine]

Threading order
Serger/overlockers have to be threaded in a particular sequence, so the threads lead correctly relative to each other.
So if you are threading from scratch (and it is best to know how !), take care to know the sequence in which your particular machine must be threaded. (If this isn’t labelled on your machine, put stickers on it to remind you.). Best to practice until threading stops being a worry. . .

And it’s also important if a thread breaks, then don’t just re-thread that one thread. For example :
– if the first looper thread which is threaded breaks, then you have to take out all the threads and thread all 4 again in the correct order.
– if threads have to be threaded in the order 1, 2, 3, 4, then if thread 3 breaks you have unthread 4 as well before re-threading. 4 has to be threaded after 3, or they will tangle up around each other.

Stretching and puckeringdifferential feed
Sometimes when you overlock, the edge of the fabric stretches or puckers. Of course there are times when you want that effect. But otherwise, the ‘differential feed’ is the fancy name for the mechanism that solves that problem.
Remove stretches / add puckers : control setting number above 1.
Remove puckers / add stretches : control setting below 1.
Basically – to make the edge shorter – increase the setting.

Video lessons

Marta Alto’s Palmer-Pletsch DVD has good exercises for exploring how to use your serger/ overlocker (I can’t understand the associated books) Sewing with sergers, Basics I and II.


Simplicity’s book Simply the Best has much information about how to use a serger/ overlocker for nearly all sewing processes.
Simplicity Simply the Best

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Originally written April 2014, links checked February 2021

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