When joining two edges that are different lengths.

Woven fabrics : gather the longer edge, to make it the same length as the shorter edge.
Knits and rib bands : stretch the shorter edge.
Make sure the difference in length is distributed evenly along the length of the seam by ‘halving and quartering’.

Gathering
Add gathering stitches along the longer edge.
Fold that edge in half and place a pin to mark the half-way fold point.
Fold the distance between end and pin, pin mark the fold to mark quarter.
Continue halving the distance between pins until the distance between pins is about 4-6″.
Do the same for the ungathered edge.

halving edges

Lay the two edges right sides together, and match up the pins,
see diagram 2 – the D shapes represent loops of fabric.

οΏΌpinning together

Pull up the gathering thread until both edges are the same length.
Add more pins, about every 1″/3cm, to hold gathers in place while you stitch,
see diagram 3.
You may like to baste before stitching, especially with weighty gathers which can pull out of position easily.

(diagrams from Bordow, Joan Wiener; Rosenberg, Sharon. The Illustrated Hassle-Free Make Your Own Clothes Book)

No more problems with uneven gathers. Hurrah πŸ‘

Actually this has a wider application than just gathers. It may be helpful when the fabric pieces are slightly different in length, and need ‘easing’ together.
Or when working around a circle such as a sleeve or body hem. If you start at one point and work steadily around, you may find you have a bulge/ lump of fabric when you get back to the starting point again. Avoid this by ‘halving and quartering’, it’s a very useful skill.

Attaching a knit neckband, or a rib band such as a cuff
A knit neckband or cuff is shorter than the edge it has to be attached to.
Halve and quarter both the band/ cuff and the edge it will be attached to.
When combining the two edges, match up the pins.
When stitching them together, stretch the shorter band so it is the same length as the other edge.

Here’s a post from Deborah J Sews about attaching a neckband, includes photos and video.

Though if you are attaching a neckband to a neckline shape which is strongly curved in some places and straight in others, you may want to attach the neckband in a way which is more individually matched to the neckline shape, see this video from Sarah Veblen at Threads.

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