Setting blocks on point opens up a lot of design options. Five years ago I wrote a post about on-point settings, including how to cut side and corner setting triangles and tips for sewing with them. Click here to go read about that. Since then I have designed and sewn several more patterns using on-point settings and I have fine-tuned my process.
Everything in that original post is still valid, but I have added point trimming to my process. The more consistent end result makes the extra little bit of time and effort worth it to me.
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| Sample on-point setting using 4" finished blocks in place of blocks. |
Why do I trim the points? Proper trimming will make the edges being sewn together perfectly matched in size, so you can pin them exactly where they need to be, from one end of the seam to the other, to avoid accidentally stretching a bias edge past where it's supposed to be.
Trimming side triangles
Adding the side triangle to a row is simple. Line up the square corner with the corner of the block or row. The tip of the triangle will stick out beyond the block/row.
The side of the triangle that will be sewn is a bias edge, and there is a risk it will get stretched. If you trim the tip off, so the side of the triangle is the same height as the side of the block/row to which you plan to sew it, you know exactly where to pin the triangle in place, precisely where it needs to be to avoid stretching as you sew.
In the example below I measured and trimmed 4 1/2" from the bottom of the triangles, to match the 4 1/2" side of the square.
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You can see below how the trimmed point matches up perfectly with the square.
Do the same thing for a triangle on the opposite side.
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| Side setting triangles sewn to both sides of the square |
My example uses just one square, but adding triangles to either end of a row of blocks would work the same way.
Please note that for all the remaining pictures I photographed the parts on my wool cutting mat instead of my cutting mat to reduce clutter in the image and keep the focus on the relevant parts of the image . Of course you should cut on your cutting mat!
Position the corner triangle over the row as you would sew it, right sides together (see previous photo). Slide the corner triangle up off the row, taking care to not rotate it and leaving it right side down.
Position the template as shown below,
so one blunt tip of the template is flush with the long side of the side triangle,
and the long side of the template is flush with the top of the row. This orients the
template properly.
Without turning the template or the
corner triangle, reposition it, again matching the sides of the template with
the sides of the triangle, and trim the point flush with the ruler.
Reposition the corner triangle over the block row, right sides together. The angles at the tips should match the angles at the ends pf the block row exactly. Pin them in place and add additional pins every 2" to 3" to keep things in place to minimize accidental stretching as you sew.
Trimming Corner Triangles - when adding to the end of a row
When a diagonal row ends at one of the corners of the quilt, you can add
the corner triangle directly to the end of the row. Again, the triangle
points will extend past the sides sides of the last block in the row.
You can trim the points even with the sides of the block. The key is to trim both points by the same amount, ensuring the 90 degree top point remains centered.
Divide the size of the block by two. In my example, the block is 4 1/2", so the measurement I need is 2 1/4". This measurement is where the top point of the triangle should fall. Let's call it the midpoint.
You can see below how to position the ruler so the midpoint measurement lines up with the top of the triangle. Make sure the long side of the triangle is lined up with a horizontal line on the ruler, to ensure your cuts will be perpendicular to the triangle base. Trim the point that extends past the ruler.
To trim the second point, reposition the ruler to measure a distance equal to the size of the block. In my example, that's 4 1/2". Measure from the previously trimmed point, and keep the base of the triangle level with a horizontal line on the ruler.
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Slide away the top row/section without turning it and position the trimming template on the bottom row/section to determine the correct orientation, matching the angle on the template with the angle on the bottom row/section.
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Without turning the template, position it over the top row/section, matching the sides of the template with the sides of the row/section, and trim away the point.
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Repeat at the other end of the row/section.
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| Row 1: Shimmering Tiles, Fabulous Phlox, Field of Leaves Row 2: Glacial, Modern Lace, Party Crackers Row 3: Sparks, Starlight Plaid, On the Fence Row 4: Fundy Skies, Triple Sunset, I Spy Lanterns |
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