Quilting is much like a puzzle. If all the pieces fit together perfectly, the puzzle will look great! When piecing patchwork, as well as when borders and sashings are added, it’s critical to use a precise seam allowance on every piece you add. If not, you risk being just a little “off”–and when that happens, it can affect the outcome of the entire quilt.
Does your machine have a ¼” sewing guideline on the throat plate? Next question: Do you trust it? Always check the accuracy of the line you are following. The same may be said about using the edge of your presser foot as a gauge–if you haven’t tested it, you may be off by just a couple of threads and not know it. That could be the reason that your pieces don’t quite fit!
Checking Accuracy
Cut two 3″ squares of 100% cotton fabric, since that’s the type of fabric you’ll likely be using for quilt piecing. Stitch the two sides together at the position you assume is the ¼” measurement according to your throat plate or presser foot. Press, with the seam allowance to one side, as you would normally do when piecing. Measure the resulting rectangle; it should measure exactly 5½” by 3”.
But I have a Patchwork Presser Foot…
Even a ¼” patchwork foot should be tested. It’s important to position your fabric exactly along the edge of the presser foot as you stitch the sample, to see if it is stitching at the right place.
Off a bit? Here’s the Cure: Add a Stitching Guide
Take a small piece of graph paper with 4 squares to the inch and place it face-up under the sewing machine needle, following the first line from the edge. As you lower the needle, shift the graph paper ever-so-slightly, so that the needle comes through the paper barely to the right of the quarter-inch line. Lower the presser foot so that the paper doesn’t budge. Make sure the paper is straight. The right edge of the paper is the measurement of a “scant” ¼”, and is where your stitching guide will be applied.
Masking tape will work, but a good choice for a stitching guide is moleskin. It’s the same product found in the foot care department of the drug store; it’s soft, has some depth but not too much, and is sticky on the back. If you prefer to use masking tape, apply several layers because you want a tiny ridge that will guide your fabric. Even if your throat plate measurement is accurate, it’s nice to have that little ridge. Moleskin is easily removable if you’d like to get it out of the way. Just use rubbing alcohol to remove any resulting stickiness before you start a different type of project. Another easy-to-remove guide is a stack of a few pages from a small adhesive note pad.
But shouldn’t my seam be exactly ¼”? Why did I need to move the paper a tiny bit before placing the guide?
Remember pressing both seams to the side? Often you’ll lose a thread or two of measurement when you turn the fabric and press. The scant ¼” seam allows for that miniscule–but important–turn of the fabric. Do a test stitching sample again, and adjust as necessary according to the outcome. Measuring more than 5½”? Move your guide a tiny bit to the right and try again. Move it to the left if your fabric sample measures less than 5½”.
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Even a few thread widths can make a huge difference when added together over the surface of a quilt. Test it–mark it–then you can forget it! Enjoy quilting without the frustration of piecing inaccurately. All it takes is a scant ¼” stitching guide!
–Ann Hammel
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