My 1940's dress pattern has side gatherings in the top (front and back). It looks like you cut a slit and gather the bottom part to make the design. You cut a stay 2" x 3" to stabilize the area. What would the stay be made out of? Fabric, or interfacing, or ?? I will be reenacting with the dress and want to be authentic.

Any ideas?

Thanks so much

It's been a long time since I've sewn anything with a stay but I believe it's a flexible piece of plastic encased in fabric. You can get them in the notions department at JoAnns or other fabric store. Are you putting it in a side seam? I believe it's to help the dress stay up.

You can still find stay at Hancock Fabrics and online at lingerie sewing supply shops.

Yes, I agree. Stays are made of plastic and help hold the form of the item you are wearing. They come in different sizes and used to be made out of whale bone a long time ago.

Seems to me that I vaguely remember some dresses that came with, or were made with side seam buttons under the left arm. (Zippers now?)

I'm wondering if it has the opening under the arm or in back or front? Some of the dresses from that age were made more or less to fit a body that no longer exists and would take a lot of muslin fitting. Or a dressmaker's dummy.

I know that the stay now is plastic and makes collars stay in shape, but this is a very old pattern. I think it is more of a stabilizer thing. The slit at the top of the dress is the place that combines the lower gathered portion. I believe it prevents stretching and supports the gathered part.

If I'm not mistaken, a "stay " is a narrow bone type item used to stabalize and shape a segment of a garment..
They were used many years ago ......
Anyone have a comment?

You still use them in strapless formals.

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Yup, that's right, a "Stay" was what others called a corset!! So it's something that causes soft things to stay in one place. And the picture THAT brings up makes me want to sit up straight and stick the girls out....I'll have to remove them from my front pockets where they were resting....

In dressmaking the little piece of fabric is used to re-enforce the slit seam. They have a tendency to tear. I used a small piece of iron-on interfacing. Do not use anything stiff as previously described or you won't be able to sew the seam. Your pattern instructions may show a picture of the stay on the wrong side of the pattern piece. I wish I was near so I could show you, not a big deal if you can see how to do it. You can sew it without the "stay" but it may tear at the point of the slit when you wear the garment.