When you sew a pair of modern pants, fairly fitted and made in woven, chances are you will be instructed to “ease the front inseam into the back one”.
In these cases, the designer made the back inseam a wee shorter than the front one, to better fit the tight area. The upper section of the back inseam, being curved, is cut on the bias. This will give the fabric enough stretch to fit in the front inseam, which is longer.
This is how I have designed my new pattern, coming really soon as part of the new One Thimble e-zine, the Justin Pants (drop crotch unisex pants for kids 2 to 16 years).
Other times you might be sewing pants where the back inseam is longer than the front one (especially in old-school man’s trousers). Then you have the situation when the inseam are exactly the same length for both the front and the back (like for any knit pants).
Now, you might be wondering: how do I sew together two pattern pieces when they aren’t the same length? How do I make sure I don’t create unwanted tiny tucks or creases? Let me show you how I do!
Note that if your pattern was designed the opposite of mine (with the front inseam shorter than the back one), you can still use this technique to ease it in! Just make sure you invert the front and the back positions in the instructions below!
How to ease in a pants inseam
Since the difference between the two pieces, in this case, is minimal, I will show you my favorite quickest method: how to pin-ease two fabrics.
Sew the crotch and the outer seam and finish the seam allowances as per the pattern instructions.
With the front leg on your sewing table, right side up, aligns the back leg on top of it, RST.
Pin the crotch seams together. Notice the extra fabric at the hems height? Let’s take care of it!
Pro Tip: Put pins on the back leg pieces, so they will be easier to pull out later, while at the sewing machine.
Pin the inseam front to back with a 1:1 ratio, until you reach approx the knee level, on both legs.Pin-ease in between the crotch and the knee, on both sides: start placing one pin in the middle, equally distributing the front inseam exceeding fabric on both sides of the pin.Go on pinning on both sides of the first pins, always spreading the fabric excess on both sides of the pin itself, until you feel comfortable in putting it under the presser foot.
Stitch the inseam (purple), with the front leg toward the feed dogs to aid you easing in the extra fabric. You might also need to slightly stretch the back leg to make it fit.
Make sure you don’t sew over pins but pull them out while they approach the presser foot.
I usually add a second row of stitching, 1/8″ from the first seam line, approx knee to knee, to add strength to the crotch (yellow).
The last touch to make this seam perfect will be steam-pressing it over a tailor’s ham, to refine the shape before you finish the seam allowances.
This will ensure you a perfectly sewn inseam, every single time!
Easing in other seams
Other times you might need to sew together two fabrics with more length difference (like on cap sleeves).
For this kind of needs, you’d better try crimping, or even ease stitching (which works like a gentle gathering) because pin-easing won’t be enough to make rid of all the extra fabric.
Other seams that might need to be eased in:
- princess seams
- sleeve’s cap
- as a substitute to elbow darts, bust darts, neckline darts or shoulder darts, to add a smidge of fullness.
Please let me know if you ever use this pin-easing technique, I’d love to hear back from you!