What_size_should_my_triangle

Tips and Techniques

What Size Should My Triangle Be?

Situation 1 - When you know the finished length of the long side of a triangle, multiply that number by .707 to get the length of the short sides. Then, add 7/8" (0.875) to each side for seam allowances.

Example: I want a triangle where the long side, when sewn, will measure 2".

Multiply 2.00 x .707 = 1.414 inches
To this total, add 7/8" or 0.875
1.414 inches + 0.875 inches = 2.29 inches

I will cut a square 2.29 inches on each side, and cut it diagonally IN ONE DIRECTION to make triangles that, when sewn, will measure 2 inches on the long side.

Situation 2 - When you know the finished length of the short side of the triangle, multiply that number by 1.414 to get the length of the long sides. Then, add 1-1/4" (1.25) to each side for seam allowances.

Example: I want a triangle where each short side, when sewn, will measure 2".

Multiply 2.00 x 1.414 = 2.828 inches
To this total, add 1-1/4" or 1.25
2.828 inches + 1.25 inches = 4.08 inches

I will cut a square 4.08 inches on each side, and cut it diagonally in BOTH DIRECTIONS to make triangles that, when sewn, will measure 2 inches on each side.

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