Some blocks look like a puzzle with no starting point. You cannot tell where one seam begins and another ends, and the instructions say partial seam, which sounds like something to leave for later. Sherri McConnell of A Quilting Life walks through one of these blocks with a square and four rectangles, and it takes four minutes.
The idea is that one seam waits. She sews the first rectangle to the square starting at the outer edge and stops about halfway along, leaving the rest of that seam open. That short seam is enough to hold the first piece in place and to make the next side long enough for the second rectangle. Then the third, then the fourth, each one going on as a normal full seam, each one making the next side ready.
By the time the fourth rectangle is attached, the block is the right size, and the only thing left is the seam she started with. She goes back, sews from the inside out to finish it, and presses. Nothing about the finished block shows which piece went on first.
The Quilter's Bible covers the same construction under machine piecing, where these are also called right-angled seams or part-sewn seams, with the same order: sew the last rectangle along the remaining edge as a full seam, then pin the hanging portion of the first seam and sew the rest of it.
What Sherri says at the end is the part worth keeping. This is a technique people skip over because they are not sure what the instruction means, and knowing it opens up patterns that were previously off the list. She has a quilt in her Sunday Best Quilts book that uses it.
The next step is our guide to partial seam quilt blocks, with the size chart, the pressing directions and a free one page sheet. Sherri's other tutorials are on the A Quilting Life channel.
