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Easy-to-Make Dollhouse Quilts If you've read Rodale Press's Classic American Quilt Series, you've read other books by Janet. She was the freelance writer for eight out of ten books in that series, and continued writing and editing for other Rodale quilting books. She has also been a contributor to other topnotch quilting publications. |
Sewing an Accurate Quarter Inch Seam
Before you begin machine piecing, it's important to set up your sewing machine to sew an exact quarter inch seam, the standard seam allowance used for quilts. Unless you use a freehand method such as foundation piecing, sewing precise seam allowances is critical for the accuracy of your blocks. If seams are not accurate, unlike blocks will not align with each other when it's time to assemble the quilt. Seam variations inside a block will even cause problems when assembling groups of identical blocks. Sewing accurate seam allowances produces sharp points, crisp corners, and helps you match-up blocks during quilt assembly. What Happens when Seams Are Not Accurate? We calculate patch size based on quarter inch seams. If seams within blocks are not accurate, the blocks become smaller or larger than they should be and the patches within them don't come together as they should to exhibit the shape they were meant to produce. Here's an example of a problem you might encounter if your seams are not accurate. Snowball blocks have only two seams per side, while star blocks have five (one between star points isn't visible below). If your seam allowances are wider than they should be--the most common problem--the star block, with its many internal seams, will be smaller than the snowball block. The end result--blocks won't match-up during assembly without some tugging, which distorts the block.
Matching identical blocks is a problem when seams aren't consistent. You'll have a hard time matching up patches in something as simple as the nine-patch blocks below if some of your seam allowances are quarter inch and others are slightly more or less.
Fine Tune Your Quarter Inch Seam Allowances Read about rotary cutting basics and accurate pressing before you begin to check and fine-tune your seams.
If Strips Are Not Accurate
If everything appears to be accurate, but strip width is still off, you may need to adjust the way you gauge a 1/4" seam. Cut several more 2" wide strips of fabric to use in test units. Sew a new set and measure carefully after each change to your machine setup.
Making a Seam Guide If seams are still not accurate, or if you are not using a 1/4" presser foot, consider marking a sewing guide directly on the machine's throatplate.
Scant Seams & Rotary Cutting When you have adjusted your seam width to sew an accurate seam allowance, it's likely you will sew what we call "scant" 1/4" seams. Why? Because rotary cut pieces are usually slightly smaller than their template-cut counterparts due to the absence of marked lines. That old pencil line was a tiny width, but most of us tended to cut on the outside of it, adding a bit of excess. The width was often just enough to compensate for the loft that gets lost in a seam when it's pressed up and over the thread. Think of that missing line whenever you measure strips or sew seams. It won't take long until you know exactly where to cut and where to sew to achieve accuracy. Pressing Open, Instead of to One Side Some quilters prefer to press machine-pieced seams open, rather than to one side. I have pressed seams open when making miniature quilts and wallhangings, but have not personally chosen to do that for large quilts. Most quilters feel pressing to one side helps strengthen the seam and also helps them match seams up for sewing. I think the verdict is still out on increased strength, but the matching-up issue is a matter of preference. To match pressed-open seams, you simply stick a straight pin through the seam lines on adjoining patches to line them up exactly, then continue aligning the remaining edges. I generally do not like to use straight pins at all when I'm sewing, so I'd rather have seam allowances that butt into each other, allowing me to do away with pins. You might prefer the security that pins provide. It seems to me that pressed open seams tend to unravel a bit at the ends if the blocks lay around awhile before they are assembled into a quilt, but that can be avoided by tying a (very gentle) little knot in the two threads at the end of each seam before you trim back the bulk of the string length. Pressing seams open creates less bulk on the back side of the quilt top. It also helps you sew a true 1/4-inch seam, because less fabric becomes tied-up in the pressover. Like many other quilting tasks, there are no absolute "right" or "wrong" ways to sew a seam. What's important are the techniques that work for you. Try pressing seams open to see if you like the results. Recommended Rotary Products Olfa NCM L 24" x 36" 3 layer Rotary Cutting Mat in Green Olfa RM CLIPS/2 23" x 70" 2 Piece Continuous Grid Rotary Mat Set in Green Olfa RTY 3 60mm Deluxe Manual Rotary Knife Blade Fabric Cutter Shop for Fabrics Online:
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