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    Make Accurate
    Triangle Squares
    Any Size!
    No Fractions or Trimming

    HST Blocks - Guidelines4Quilting

    Choose a whole-number
    finished size on your ruler.
    The exact seam allowance

    is automatically added

    Triangle Squares - Guidelines4Quilting
    HSTA - Finished size and Seam Allowance on the Ruler - Guidelines4Quilting

    1) Attach the Half-Square Triangle
    Addition to your quilt ruler.
    Line up with the selected
    whole number to cut strips.

    Seam Allowance Additions - Guidelines4Quilting

    2) Cut the squares
    diagonally in half.
    Your triangle squares finish at
    the selected whole-number size
    with the exact seam
    allowance already included.

    Seam Allowance Additions - Guidelines4Quilting
    • 9-Patch Blocks:
      1″ HSTs make a 3″ block
    • 2″ HSTs make a 6″ block
    • 3″ HSTs make a 9″ block
    Make These Using Seam Allowance Additions by Guidelines4Quilting
    • 16-Patch Blocks:
    • 1″ HSTs make a 4″ block
    • 2″ HSTs make an 8″ block
    • 3″ HSTs make a 12″ block
    Seam Allowance Additions - Guidelines4Quilting

    Half Square Triangle
    Seam Allowance Addition

    (Rulers Not Included)

    Seam Allowance Addition for Half Square Triangles - Guidelines4Quilting

    No Trimming

    because the H Addition automatically adds the exact 0.854″ seam allowance. With standard quilt rulers marked in ⅛″ increments, quilters have no choice but to add ⅞″ instead—almost 1/32″ too much.

    Made of unbreakable polycarbonate
    Left-handed Friendly

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    how to make diamond in a square quilt blocks any size

    The 12″ Addition attaches firmly
    with premium suction cups
    featuring easy-release tabs.
    Get two for your 24″ ruler.

    Seam Allowance Additions - Guidelines4Quilting

    Your triangle squares will
    match your squares perfectly.

    Shoo Fly Quilt Block | Guidelines4Quilting
    Quilt Block - Guidelines4Quilting
    Quilt Block - Guidelines4Quilting
    Quilt Block - Guidelines4Quilting

    Make Accurate
    Diamond in a Square
    Any Size
    No Fractions - No Trimming

    Cut squares diagonally in half.
    The exact amount of
    seam allowance
    will be automatically added.

    how to make diamond in a square quilt blocks any size
    Cut Half Square Triangles - Guidelines4Quilting

    Use the Prep-Tool for
    - Pre-trimming HSTs
    - Sharp Mitered Corners
    - Precise Set in Seams

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    Short-Side Trim
    Align the Prep-Tool
    on the long side for
    Diamond-in-a-Square

    Long-Side Trim
    Align the Prep-Tool
    on the short side for
    half square triangles

    Your HSTs will
    match squares


    Quilt Ruler Connector / Handle

    quilt ruler Connector by Guidelines4Quilting
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    Rulers work for straight cuts
    like squares and rectangles.

    square and rectangle

    To make half square tangles,
    you need to cut squares
    diagonally in half.

    HST and QST
    Seam Allowances for HSTs - Guidelines4Quilting

    The problem is that
    your rulers only have
    lines every 1/8".

    6 women
    • So, you add 7/8" to compensate,
      which is almost 1/32" too much.

    That's why quilters make HSTs
    a little bigger, and then trims them down to match with squares in the same block.

    The Half Square Triangle Addition
    lets you add the precise amount
    of seam allowance, 0.854",
    right on the edge of your ruler.

     

    No More Trimming!

    Your triangle squares will
    match with your squares.


    Seam Allowance Additions

     

    Make Squares
    Half Square Triangles
    Quarter Square Triangles


    Any Size. No Math!

    how to make diamond in a square quilt blocks any size

    Seam Allowance Additions

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    Get 2 for your 24" ruler

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    Using Grip Strips on
    Your 12" & 24" Ruler?

    If you already have Grip Strips on your rulers, you'll also need to put one on the edge of your Seam Allowance Additions.
    Make Sure
    Everything's Level:

     

    Grip Strips

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