Pinning Quarters for Undies

 I’m finishing up some underpants for my littlest girl. I made her a trial pair and she said the crotch area was a bit tight. The elastic in the pattern is put on the legs in even quarters. So, I asked some sewing friends and they suggested an uneven distribution. 

While pinning the last pair’s leg holes, I thought I’d get some pictures to show how I do this. I’m actually going to pin them in eighths because of how the quarters lay and which are easier to pin on this pair.

First, I fold the pants so the wide seam is about centered in the gusset:

The green pen is aimed at the side seam (where the serger threads are attached) and about the center of the gusset. This isn’t always perfectly centered, so after I pin the folded edges, I refold so these pins are touching.

In the second picture, the gusset and side seam area are pinned. The back side is convex and front edge is concave, so this has to be adjusted somewhat to even it out. Sometimes the “side seam” pin is off by a small amount.

The next thing is to mark halfway between each of these quarters. On this pair, I’ve used the yellow pins.

These pins that wind up close to the ends of the gussets on the crotch side and high on the back and front edges are in a better spot for my elastic to focus its stretch.

Along the front edge, I want to give the leg a bit more elastic to stretch and move, but against the backside, I want the elastic to snug in a bit and hold the fabric next to the cheek. 

In order to do this, I fold the elastic in half, then give the front a bit of the back’s half. In this pair, it will be about an half inch. Then I’ll quarter the elastic and connect it to the underwear. This gives the back about 75% stretch on the elastic compared to the fabric, and the front doesn’t stretch quite as much.

The blue pin on the left marks the halfway point from the blue pin on the right. The yellow pin shows the adjustment for more elastic on the front half than the back half. Next, I’ll remove that extra blue pin from the left and pin halfway between the right blue pin and the yellow pin, on both sides. Note: I find pinning the elastic in eighths gives me just a bit better control, so I’m not taking the extra pins from the leg edge. Once I pin the longer front edge into the leg, I’ll pin the elastic for the back and pin that in. 

 Pinned in, the back leg edge has a bit of looseness (about 75% elastic to fabric), and the front edge almost matches. The elastic on the front will barely need to be pulled (about 90% of the distance).

On first pass, the leg cinches in nicely, but the gusset isn’t pulled too tight.

Done!