Learn How to Sew Knife Edge Quilt Binding

Quilting Tips and Techniques
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It's easy to learn how to create a knife edge finish around the edges of a quilt. The method is often called knife edge binding, but (in most versions) the finished product isn't truly a separate binding. Instead, it is a finish that's created by folding under excess fabric along the edges of the quilt top and quilt backing, and then sewing those edges together.

A knife edge finish is flatter when it's used to connect quilts with borders because blocks with lots of seam allowances can be a bit bulky around their edges, but you may find that the technique is perfectly acceptable for most quilt tops.

A low loft (thin) batting creates a neater knife edge finish.

When is a knife edge finish a good choice?

  • A knife edge finish is not as durable as typical binding, so reserve the method for miniature quilts, landscape quilts and other types of wall hangings and quilts that will be used (lightly) for interior decor.
  • Potholders, table runners, and placemats are other possible candidates for knife-edge finishes.
  • Knife edges might be a good choice if you'd like for the outer perimeter of a quilt to appear more streamlined, without the added bulk of a typical binding.
  • Try the technique for quilts with irregular edges, such as a Grandmother's Flower Garden quilt that retains its hexagon perimeter.

When Should a Knife Edge Finish Be Avoided?

Baby quilts and bed quilts are laundered often and experience more wear -- a knife edge finish would not be as durable as double-fold binding for either type of quilt.

How to Finish a Quilt with a Knife Edge 

  1. Sandwich the quilt with batting and backing and quilt it as you normally would, but stop quilting about an inch from the outer edges of the quilt top.
  2. Carefully square up the edges of the quilt to remove excess batting and backing.
  3. Fold one side's backing and quilt top away from the batting, leaving only the batting exposed.
  4. Use rotary cutting equipment to trim away 1/4" of the batting. Take care not to trim the quilt top or the backing.
  5. Repeat to trim the batting on all sides of the quilt, removing the same amount of batting from each side.
  6. Starting on one side, fold the backing up and over the batting and pin to secure the edge. Fold and pin the entire side. Check to make sure the fold-overs are equal.
  7. Turn the quilt top under, matching the top's folded edge to the already pinned side, removing pins (one at a time) as you work and inserting them again to hold both turned layers in place -- folded edges should match exactly.
  8. Sew a row of basting stitches through the turned-under fabrics. Basting holds the folds in place and allows you to remove the straight pins to avoid pinpricks.
  9. Fold under corners as needed to create a smooth, lump-free transition from one edge to the next.
  10. Turn under the remaining sides in the same way and baste.
  11. Use a blindstitch and a thread that matches or blends with fabrics to connect the top and backing along each side. Sharps needles, which are used for applique, are a good choice for this type of seam.
  12. For quick projects, such as potholders, you could omit the blind stitch and machine sew a seam around the quilt, placing it about 1/8" from the outer perimeter to secure folded edges. Some quilters do this after blind stitching, but it isn't necessary and you might not like the look.
  13. Quilt within the 1" unquilted area if you like, but take care to avoid puckers.

Batting can be cut back more for quilts when the quilt is surrounded by borders since you don't have to worry about infringing on the built-in quarter-inch seam allowance that exists on the outer edges of quilt blocks.