Tuesday, December 29, 2015

Tuesday Tutorial: Setting Triangles

For some reason, I've recently been enamoured with triangle-set quilts!

(You're not imagining things. Not all the rows are finished!)

The challenge with this setting is -- how big do I cut the setting triangles?  For example, my Summer "A Quilt Block a Day" quilt is made up of blocks that are 6½" raw-edge-to-raw-edge. The pattern I based my quilt on calls for 10½" squares cut in half diagonally for the setting triangles.

The only problem with this method is, the outside (long) edge of the triangles will be on the bias. 

Having a bias edge on the outside edges of the quilt can result in a wavy quilt. It is possible to reduce this problem by sewing a row of stay-stitching right next to the outside edge.

Or you can use a setting-triangle tool and cut the setting triangles with the straight-of-grain on the long side (hypotenuse)  of the triangle. Here's how I cut the setting triangles for my "Birds in Flight" quilt.

1. Cut a strip of fabric one-half MINUS one-eighth inch the size of square called for in the pattern. My pattern required a square cut at 10½" so I cut my strip 5" wide.

2. I have several setting triangle rulers. The Nifty Notions ruler is similar to the EZ Angle Companion Angle ruler. But neither has a  " marking.

3. I love Marti Michell's templates and rulers. The Diagonal Set Triangle ruler #8968 can be used for both corner triangles and setting triangles. To make a side-set triangle, place the ruler on the fabric strip with the 5⅛" mark at the bottom of the cut edge. Cut along the right side only:

4. Flip the ruler to the left side (the writing will now be reversed!). Carefully line up the notch at the top of the ruler with the cut you just made:

(see how I have the top notch aligned with the previous cut?)

5. And make the cut along the left side. 

6. To attach the setting triangle, line up the 90 degree angle with the right-hand corner of the block.

7. Stitch and press -- because I'll be sewing rows together, I pressed all the seams on the odd-numbered rows to the left, and all those on the even-numbered rows to the right.

8. Notice that the triangles are about ½" bigger than the blocks. This makes it possible to trim the setting triangles to exactly ¼" beyond the intersection of the rows. Or I can leave them "floating!"

Come back Friday for the last UFO Parade of 2015!

From the desk of your auntmartisignature


  1. Great tutorial! Thanks so much....again!

  2. Thanks for this! Love your quilt!

  3. Great tutorial! Coincidentally, we are making the Birds in the Air blocks for the Block Lotto this month, so I shared the photo of your blocks as a setting idea and linked to your tutorial on Blocklotto.com (if that's NOT OK, let me know ASAP and I'll take it down.)

  4. Gosh, a new ruler to pick up at the next quilt show! I am doing the Bonnie Hunter mystery quilt, and she gave us the sizes of setting triangles to cut, on the diagonal, naturally. There is a narrow border next to those setting triangles. Should I still stay stitch? Very curious.

    1. I would stay stitch both if the setting triangles are the very outside AND if there will be another border after. Use a slightly smaller stitch and sew 1/4" from the edge.


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