Machine Pieced Clamshell Tutorial

Clamshell Tutorial-8-2 copy

Jessie and I decided to do a private swap back in September. As I was "stalking" her, I saw a lot of clamshell quilts in her favorites and on Pinterest.

I'm not much for hand-sewing though. You've probably realized that by now. ;) So I figured out a way to sew them by machine. The look is similar, but not exactly the same.

Curve Templates (I used these designed by Christina)
- 4 - 4" squares of each fabric (if you use different templates, you might have to adjust the size of your squares)
- rotary cutter, ruler, mat

Make It!
1) You will need 2 concave curves and 2 convex curves. It's best to cut the same pieces at the same time, but right sides together so that they are mirror images. Pay attention to directional fabrics.

2) This step is very important. You will need to lay out all the pieces to make sure that they are sewn together in the right order. It will look a lot larger now than it will be when sewn together. (There are 2 pieces missing due to (ahem) technical difficulties. Picture on the right shows top row sewn together for shrinkage comparison.)
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3) Keeping the curve pairs together, sew the curves. There are a lot of different ways. Here's what I do:
a) Mark the centers of the concave and convex curves. Line them up and pin, making sure the concave curve is on top (the picture on the right has the pin on the WRONG side).
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b) Align the ends.
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c) Sew together using a 1/4" seam allowance, matching the seams as you go. Try not to stretch too much.
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4) Press all curve seams toward the convex curve. You want to press them this way, regardless of the light/dark fabric because you need the seam allowance out of the way for the next steps.

5) Trim down the blocks 1/4" outside the curve on the concave side. Square up to 3.5" x 3.5"
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6) Sew blocks together in pairs, making sure you align curves. Press seams open.
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7) Sew pairs into rows, then sew the rows together. As you are sewing together the blocks, you will be sewing very close to your curve seam. Press all seams open.

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DONE! Sandwich, quilt, bind, enjoy.

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I opted to quilt  mine using 6" circles offset from the blocks. I was inspired by Amanda's perfect circles, but I used my walking foot for these since they are so large.

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  1. This is such a great way to make the clamshells! And your pillow is so cute!

  2. super cute, Ali! I <3 Clamshells but don't have the time or patience to handsew them! I want to give this a try :)

  3. Holy wow this is adorable! You make this look really simple and now I have to add it to my future project list. Darn.

  4. Ali, this is awesome! I've been wanting to try these forever, but like you, not so keen on the hand-stitching part. Thanks for figuring this out.

  5. Who would have 'thunk' that it'd be that easy? Thank you for enlightening me!


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