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Corner Beam

Diagram of the Corner Beam quilt block layout
Design with this block

Techniques used (complete these first)

Corner Beam Unit

Corner Beam Unit

Build a wedge beam with mirrored side triangles, then trim to exact unfinished size for sharp points and stable outside edges.

  1. Cut center-beam patches from squares (not strips) so the long outside edge stays on straight grain.
  2. Cut side triangles in mirrored pairs by folding fabric right sides together or wrong sides together before cutting.
  3. Sew one side triangle to each long edge of the center beam, matching the long triangle edge to the beam edge.
  4. Press seams away from the center beam to reduce bulk at the narrow point.
  5. Trim each unit to unfinished size, aligning seam placement so the beam point lands correctly after 1/4 inch seams.

Pro tip: Always cut side triangles as mirrored pairs; if both are cut in the same orientation, one side of the beam will twist and point alignment will fail in final assembly.

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.

Block Assembly

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

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