The Elusive Scant Quarter Inch Seam Allowance

Scant quarter inch

So you’ve heard you should sew your blocks at a “scant quarter inch seam allowance” and wondered what the heck that means? You’re not alone. In this video, we’re going to unravel the mystery of what a scant quarter inch is, explain why it’s important, and show you exactly how to achieve it every time you sew.

Please watch my video for a full explaination and detailed information. Please hit the like button if you thought it was helpful!

Let’s kick things off with the basics: what is a seam allowance? Simply put, it’s the gap between the fabric edge and where you place your stitches.

But here’s the million-dollar question: why isn’t a regular ¼” seam allowance sufficient?

Well, it all boils down to the space taken up by the thread and the fold of the fabric. It might not seem significant, but believe me, when you’re piecing together multiple sections, these tiny differences start to accumulate. For a clear example, take a look at the image below. I’ve stitched together three 2½” x 2½” squares using a standard ¼” seam allowance. Ideally, the middle piece should measure exactly 2″ in width. However, as you’ll notice, it’s just slightly less than that.

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In the image below, I used a scant ¼” seam allowance, and you can check out the difference it makes. This time, the middle square is measuring exactly 2″. Just this tiny adjustment in how we sew can lead to perfectly sized pieces. It’s a small change with a big impact, ensuring everything lines up just right in our projects.

To clarify, a scant ¼” seam allowance means sewing just a smidge less than a quarter inch—essentially, a thread or two shy of the measurement. This slight reduction compensates for the thickness of the thread and the fabric’s fold, ensuring that the finished size of pieced sections is accurate and consistent.

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Nailing that scant quarter inch seam is simpler than you might think. If you’re already comfortable sewing a regular quarter inch seam, you’re halfway there. The key is to make a small but crucial adjustment to make it slightly narrower. Here’s how you can do it:

  1. Special Foot: If you use a quarter-inch presser foot, check if it’s adjustable or if there’s a “scant” version available. Not all feet are created equal, and some are specifically designed to give you that scant quarter-inch seam with precision.
  2. Tape or Guide: Place a piece of tape or a magnetic seam guide on your sewing machine as a visual guide. Position it just a tad closer to the needle than you would for a standard quarter-inch seam. This slight shift can make all the difference.
  3. Needle Adjustment: Many modern sewing machines offer the option to adjust the needle position. Moving the needle just one position to the right (or left, depending on your machine) can create the perfect scant quarter-inch seam allowance.

By incorporating these adjustments, you’ll find that achieving a scant quarter-inch seam becomes second nature. This minor tweak can significantly impact the accuracy of your piecing, leading to more precise blocks and a better overall finish in your quilting projects.

Scant quarter inch

Fabric used is Picture Book by Kimberly Kight for Ruby Star Society.

Products To Help With Your Scant Quarter Inch:

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It’s important to note that a scant ¼” seam allowance isn’t always a must—for instance, when working on straightforward projects like an I Spy Quilt or a Rail Fence Quilt, where uniform blocks come together without the need for precise finishing sizes. When it does matter is when you want you blocks to finish at an exact size, so for our Mystery Block of the Month we are making a sampler quilt with 12 different blocks, we need each block to finish at the same size. But remembering if you need to you can always cut all your blocks down to your smaller size as well.

Pin it! Would you like to refer back these ¼” Seam Allowance later? Don’t lose it, pin it now to one of your boards on Pinterest!

Scant quarter inch

And if you have any suggestions for other projects you’d like to see, feel free to drop me a line! Sewing is my passion, and I’m always happy to share my love for it with others.

Thanks again for stopping by, and happy sewing!

Stacey x

Shop Fabric at Fat Quarter Shop

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