How to Stretch Elastic Evenly When Sewing (Without Losing Your Mind)

Ever sewn underwear, swimwear, or gym wear and ended up with elastic that’s … well … a bit of a disaster???

You know what I mean – wavy like the ocean in bad weather, squeezed to death in one place and flapping about in another. Or maybe the whole thing looks like it survived a washing machine on the spin cycle 😅

If you’re sitting there thinking “How much do I even stretch this thing???” and just … guessing … then yeah, I’ve been exactly where you are right now.

So here’s what I’m going to show you – a dead-simple ruler trick that’ll save you from all that wonky elastic nonsense. No maths degree required 😏

By the end of this??? You’ll know exactly how to get perfectly even elastic every single time. And you’ll wonder why nobody told you this years ago 🙄

Why should you listen to me??? Well, I’ve been sewing for over a decade, specialising in underwear and swimwear. My first 10-11 pairs of knickers??? Absolute disasters 😂 Some looked like premature baby pants (way too tight), others were wavy. One leg would be squeezed to death while the other flapped about … I’ve been there, done that, got the rubbish knickers to prove it. And by the way if you are new here I’m Alyona)))

The Struggle is Real (And We’ve All Been There)

Right, let me guess … You’re sat there with your lovely fabric, your elastic, and your sewing machine, thinking “How much do I stretch this thing???”

And then you just … wing it 🙄 Stretch it a bit here, stretch it a bit more there, and hope for the best.

Ten minutes later you’re staring at your creation wondering if you’ve accidentally made a garment for someone with one leg twice the size of the other … Because sure, that’s totally what you were going for 😂

Here’s the thing – even after sewing underwear for more than a decade, if I don’t touch my machine for a week or two, I STILL struggle to get that muscle memory back!!! My hand forgets how much to stretch, and it takes time to find that sweet spot again.

So if you’re a beginner??? Confident sewer??? Doesn’t matter. This problem doesn’t discriminate. It’ll get you when you least expect it.

The One Tool That Changes Everything

Ready for this life-changing revelation???
A ruler.
Yep, that’s it. A simple soft tailor’s ruler 😏

(I know, I know … you were probably expecting some fancy gadget that costs a fortune. Nope. Just a ruler. Revolutionary, isn’t it???)

Here’s Exactly What You Do

Step 1: Stick That Ruler On

Grab your soft tailor’s ruler and stick it to your sewing machine right where your needle starts.

Put your sewing foot up, needle down, and position the ruler against the needle at the front. Then shift it slightly to the right.

Use a bit of scotch tape to stick it down. If you’ve got a spare ruler, you can leave it there permanently. If it’s your only one, just stick and unstick it as needed (no judgment here 😂).

Step 2: Do a Test Run (This Bit is Important!!!)

Before you go anywhere near your actual garment, grab some scrap fabric and the elastic you’re planning to use.

Now here’s where you get to decide – how stretchy or not-stretchy do you want your elastic???

And honestly??? There’s no right or wrong answer here.

Some people love that wrinkly, ruched style where everything’s pulled tight. Others want that flat, Instagram-perfect look where the garment sits completely smooth on a surface 🤷‍♀️

The ONLY wrong way is stretching the fabric instead of the elastic – that’ll give you horrible waves, and nobody wants that …

So here’s what you do:

• Put your fabric and elastic under the needle
• Put your foot down
• Look at that ruler you just stuck on
• Grab your elastic with your fingers at, say, the 6cm mark
• Stretch it to 8cm
• Sew it onto the fabric

Do this a few times, then check your scrap piece. Happy with how it looks??? Brilliant 🙌 Too wrinkly??? Stretch less (maybe 6cm to 7cm instead). Not wrinkly enough??? Stretch more (6cm to 9cm).

Play around until you find YOUR perfect stretch.

Step 3: Now Do It For Real

Right, you’ve found your magic number. For me, with the polyester fabric I use, a 2cm stretch works perfectly – that’s grabbing at 6cm and stretching to 8cm.

Now take your actual garment.

If you’re using picot elastic, place it on top of your fabric.

If you’re using fold-over elastic (and honestly, if you’re a beginner, START WITH THIS ONE – it’s so much easier to manage 👍), pop your fabric in the middle and fold the elastic over.

Put everything under your needle and secure it by putting your foot down. Pop your needle down too – this helps hold everything in place so it doesn’t slide about when you pull.

Then:

1. Grab your elastic (when it’s not stretched) at your starting number – for me, that’s 6cm
2. If you’re using fold-over elastic, place the fabric in the middle
3. Stretch to your end number – for me, 8cm
4. Fold the elastic (if using fold-over)
5. Sew
6. Keep repeating until you’re done

Whether it’s leg holes or waistband, just keep going round. That’s it. Job done ✅

Can You Believe It’s That Simple???

Honestly, when I discovered this technique, I wanted to cry. In a good way, obviously 😅

Ten years ago when I started sewing, YouTube was basically naked – hardly any videos, and the ones that existed were so badly filmed you could barely see what was happening. Useful articles??? Forget it …

I spent SO much time wasting fabric, wasting elastic, and frankly, wasting my nerves trying to figure this out 😤

I wish – I SO wish!!! – I’d known about this ruler trick back then. It would’ve saved me so much hassle.

But here we are … At least now YOU don’t have to go through what I went through 🙌

Want more sewing tips and free patterns??? Pop over to my YouTube channel where I share all sorts of underwear and craft goodness 💕

What Happens Next???

Here’s the lovely bit – if you use this technique regularly, your muscle memory will eventually kick in. Sooner or later, you won’t need the ruler anymore. You’ll just … know. Your hands will automatically stretch the right amount 💪

But until then??? Stick that ruler on and take the guesswork out of it.

And if you want to test this technique right now, grab my free panty pattern. It’s super comfortable, perfect for practising this new skill, and honestly??? I’m dying to know if this works for you 😊

Drop me a comment and let me know – did it help??? Did your elastic behave itself for once??? I genuinely want to hear about it.

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