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Diamond in a Square

Diagram of the Diamond in a Square quilt block layout
Design with this block

Techniques used (complete these first)

Midpoint Triangle Join

Triangle-to-Edge Join

Attach a regular triangle to a square or rectangle edge by matching center points first, then sewing a standard 1/4 inch seam.

  1. Fold the base edge (square or rectangle side) in half and finger-press to mark its midpoint.
  2. Fold the triangle along its base to mark the midpoint of the long edge.
  3. Place triangle and base right sides together, align midpoint marks first, then align both corners and pin.
  4. Sew with a regular 1/4 inch seam from one end to the other without stretching either edge.
  5. Press the triangle away from the base and trim dog ears if needed before adding the next seam.

Pro tip: Pinning the midpoint first prevents the triangle point from drifting left or right; this is the key to keeping points centered across repeated units.

Oversize and Trim (The Float)

Triangle-in-a-Square Unit

Intentionally cutting components slightly larger than needed to allow for a perfect trim-down after sewing.

  1. Cut pieces using the 'oversized' formula (usually adding an extra 1/2 inch).
  2. Assemble the unit following standard seam allowances.
  3. Place a square ruler over the unit, aligning the center or diagonal points with the ruler markings.
  4. Trim all four sides to reach the final unfinished block size.

Pro tip: When trimming 'Triangle in a Square', ensure the top point is exactly 1/4 inch from the edge so it isn't lost in the next seam.

Subunits first

Using the techniques listed above, make the following sub units: 1 Diamond-in-a-Square Unit.

Block Assembly

Assembly instructions are currently in the works, check back soon for updates!

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