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Getting an accurate 1/4″ seam

If you’ve ever done a jigsaw puzzle that has warped pieces, you know how frustrating it can be when pieces don’t quite fit together. This can easily happen to a quilt if you’re not careful. The more accurately you cut and sew, the easier things will go together and happier with the process you’ll be. This pattern doesn’t have anything complicated, but pay attention. If you need to cut a 4 1/2” square, you can’t cut 4 3/4” and say “close enough”. Just like carpenters – measure twice, cut once.

If your fabric is cut accurately, that is half the battle. The other half is sewing accurately. Quilting uses a 1/4” seam allowance. (Seam allowances is the edge of the fabric that goes to the inside.) If you sew with a 3/8” seam allowance, all your pieces will be too small, and they won’t line up. If you sew with an inconsistent seam allowance, you will be really frustrated. Take the time to practice and find your accurate 1/4” seam allowance. It is worth it in the long run.

To find your seam allowance, cut a few 3″ squares out of scraps. It is important that they are exactly 3″ square.  If you are unsure of using a rotary cutter and ruler, here is a great video.  (It’s not me, but if I was going to make a video, I would say all of these things.)

At your sewing machine, put your ruler under the pressure foot, and line up the 1/4″ mark with the needle.


Put a post-it note by the edge of the ruler, then remove the ruler. Many machines have a 1/4″ line marked on the base, and these are a good starting point, but not always reliable.

Take two squares and sew the seam, aligning the edge of the fabric with the post-it.

Press the pieces apart. Measure the pieces. Each piece should be 2 3/4″ wide. If they are less than that, you need to slide the post-it slightly toward the needle. If they more than that, move the post-it slightly away from the needle.

Once you’ve adjusted the post-it, try again until you end up with two pieces 2 3/4″ wide.

When that is done and accurate, try adding another square onto the piece. With a proper seam allowance, you should end up with a 2 1/2″ piece in the middle.


When you’ve don’t that, you can be confident that is the place on your machine to line up your pieces. Put some masking tape at the spot to remember it, and use it to align as you sew.

Every once in a while, especially if you’re switching to a different kind of fabric or needle, you will need to check again, but it gets easier and faster every time you check it.

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