In a nutshell, it has become increasingly common to see patterns that simply cut a block in half to create a setting triangle. Personally, I have come across this three times in the last couple of weeks. The first was when I made the Nyalik quilt. The corners really bother me because the corner blocks were just cut off when squaring up the quilt.
In hindsight, it would have looked better to use solid squares and not have those random pieces on the corners. However, it is quilted and bound so it’s going to stay the way it is. In case you’re wondering, that thing in the corner is a magnet. I use magnets to hang quilts for photography.
Next, I came across a pattern where the designer called for simply cutting blocks in half to use as setting triangles. I read, then re-read thinking there must be a mistake because the math doesn’t work. In order to fit, the blocks need seam allowance on both halves and that doesn’t happen by cutting them in half.
Then, a well-known designer showed a peek on Instagram of a new pattern she is writing and shared that she also simply cuts a block in half for setting triangles. Her post went a little more in-depth to justify her technique. There were many comments about the “quilt police” and making quilts however you wish. I asked about the lack of seam allowance on both sides, and she replied that the “vast majority” of her customers would rather do this than make a traditional setting block. She also said that most quilters’ level of imprecision makes the seam allowance variance immaterial. It was a very respectful reply with her saying it was an “agree to disagree” situation.
If you have been with me for any time at all, you know that I think quilting should be as fun and stress-free as possible. I found this subject interesting because the pattern I am currently writing is for a quilt set on point. I wondered if you really could fudge that seam allowance and be happy with the results.
For this particular project, the answer is definitely, “NO!”. You can clearly see in the picture that cutting the block in half would leave no seam allowance so the corner of the four-patch would be lost when either a border or the binding is sewn on. I think it is worth the little bit of extra effort to maintain the integrity of the block.
Then I wondered if you could fudge the seam allowance if there are no points or corners to cut off. The answer to that is a little less clear. I cut an 8-1/2″ block in half, then I cut a traditional setting triangle following this formula: size of finished square multiplied by 1.414, then add 1.25″ for seam allowance and round up to the nearest 1/8″. My measurements were 8 * 1.414 = 11.312. Add 1.25″ and you get 12.562. After rounding up, I cut my square 12-5/8″, then cut on the diagonal both ways (an X) to yield four setting triangles.
In this picture, the setting triangle is on the bottom (white), and the half-block is on top (yellow). You can clearly see there is a difference in size. Is this within your fudge factor comfort zone?
This close-up shows the difference right at 7/16″ of an inch.
That would not be an acceptable result for me. One way to make it work is to ease in the block. This can result in puffing or puckering at the edges. Another way is to sew the triangle without easing, then trim the blocks even with the setting triangle. You cut off the edge of the quilt, but if it doesn’t matter design-wise, it does work.
One last, but important consideration is bias. When you cut a square diagonally into two triangles, the hypotenuse is on the bias. When set into the quilt, that becomes the outer edge of the quilt. I much prefer the stability of straight of grain made by cutting on the diagonal twice.
It really does come down to personal preference. In almost every situation, I would choose to make a setting triangle. Over the last 30 years, I have learned tips and techniques that give the best results with the least amount of effort, and love sharing it all! Even though I like to make things easy, I DO care about matching seams, sharp points, and accurate piecing. My experience is that most other quilters care about these things too. Quilting should be fun and not frustrating. That certainly doesn’t mean that one particular method is the “right” way or the “better” way, but having a solid foundation of quilting skills will help you make a decision that is right for you.
In the meantime, I am excited to finish this quilt and finish writing the pattern. The springtime palette gives me hope that spring will come as we are buried under a mountain of snow! This is a great design for using scraps, leftover 2-1/2″ squares, jelly rolls, charms, or layer cakes. It is also very easy to construct!