10 Tips to Get the Perfect 1/4" Seam
1. Check Your Stitching
Cut three 1-1/2"-wide strips of fabric. Join two of the strips using a 1/4" seam; then add the third strip with another 1/4" seam. Press the seams away from the center strip. Turn patchwork to the right side of the fabric and measure the center strip. It should measure exactly 1" wide. Reset your seam guide as necessary.
You can also check the width of a machine's presser foot by sewing a sample seam with the raw fabric edges aligned with the right of the machine's presser foot. Measure the seam allowance using a quilting ruler. (Alternatively, sew along a piece of graph paper with a 1/4" grid or an index card with lines 1/4" apart to check if your seams are accurate.)
2. Adjust the Needle Position
Needles on many machines move right or left. Sew sample seams and check each seam size as you move the needle in small increments. Jot down the needle position for each seam size so you can quickly set it as needed. When sewing, watch the guide and not the needle.
3. Change the Throat Plate
The start of a 1/4" seam is cleaner with a single-hole throat plate; threads and fabric won't sink into the hole. Be sure to change the plate before you zigzag-stitch, or the needle will break.
4. Start and End Seams with a Fabric Scrap
To prevent a patchwork seam from puckering or having incomplete stitches at the beginning or end of a seam, use a small piece of fabric to begin and end your seam. Feed the small scrap in first, then the patchwork fabrics, followed by another small scrap. Snip off the stitched scraps.
5. Purchase a Specialty Foot
A 1/4" presser foot, whether it's generic or made just for your machine, takes much of the guesswork out of sewing 1/4" seams. Run the edge of the fabric along the right-hand edge of the foot as you sew. Measure the seam before beginning each project. Some specialty feet have an attached edge guide, above, that prevents you from stitching a too-wide seam.
6. Choose a Seam Guide
Most sewing machine companies offer an easily positioned, screw-in seam guide attachment that provides an edge for the fabric to slide along. Magnetic guides, used on noncomputerized machines, also are available. You can fashion your own guide from a strip of painter's tape, masking tape, or adhesive moleskin. To set a guide, lower the needle, place a ruler or 1/4" graph paper against the front or back of the needle, and position the guide along the 1/4" line.
7. Pinning Is the Secret
When you want the seam lines in patchwork pieces to line up perfectly, first pin the pieces together with extra-fine pins. With right sides together, pin one piece to another unit, aligning raw edges. Match seams by pushing a pin through both layers to check alignment.
8. Press For Success
In quilting, almost every seam needs to be pressed before the piece is sewn to another. Pressing the seams ensures accurate piecing. The direction you press is important in piecing and usually will be specified in the instructions. When in doubt, press seam allowances toward the darker fabric. You'll usually press the entire seam allowance to one side rather than open.
When two seams will be joined, press the seam allowances in opposite directions; this helps line up seams perfectly and reduces bulk. Press seam allowances in each row in opposite directions so they abut when rows are joined.
Press, don't iron: Don't know the difference? Ironing involves moving the iron while it is in contact with the fabric; this stretches and distorts seams. Pressing means lifting the iron off the surface of the fabric and putting it back down in another location.
Setting a seam: Before pressing a seam open or to one side, press the seam as it was sewn, without opening up the fabric pieces. This helps sink the stitches into the fabric, leaving you with a less bulky seam allowance.
9. Joining Pieces, Blocks, and Rows
Precise 1/4" seams allow you to join units, blocks, and rows with ease. Use exact 1/4" seam allowances throughout a quilt's construction. With the number of seams in a quilt top, little variances can quickly multiply.
It isn't necessary to backstitch at the beginning of any seam that will be intersected by another seam later in the quilt making process. Use a stitch length of 10 to 12 stitches per inch (2.0- to 2.5-mm setting) to prevent the stitches from unraveling before they're stitched over again. Secure seams that won't be sewn across again (such as those in borders) with a few backstitches..
On the sewing machine, squares and triangles in blocks should be sewn together from edge to edge. Save time and thread by chain piecing whenever possible. To chain-piece, feed the pieces under the machine needle. Don't lift the foot or clip the thread. Short lengths of thread will link the stitched patches. Cut them apart when you've finished sewing the units.
10. Sewing-Machine Troubleshooting Tips
While it's a good idea to take your machine to a dealer regularly for a tune-up, here are a few fixes for common problems.
Bad stitch quality: Before making any other adjustment, lift the machine's presser foot and rethread the machine.
Skipping or uneven stitches: Try replacing the needle with a new one. Although some quilters only change a needle when it breaks, a smarter rule of thumb is to insert a fresh needle at the start of every project (or every 8 hours of sewing).
Thread breaking: If you're using old thread, try a new spool; old thread can become brittle and lose elasticity.