Seam Allowance Addition
for Half Square Triangles
Made of unbreakable polycarbonate
Left-handed Friendly
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Make Triangle Blocks
Accurately!
Any Size. No Math!
Make Accurate HSTs Any Size
No Fractions. No Trimming.
(Rulers Not Included)
Cut squares diagonally in half.
The exact amount of
seam allowance
will be automatically added.
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
Rulers work for straight cuts
like squares and rectangles.
To make half square tangles,
you need to cut squares
diagonally in half.
The problem is that
your rulers only have
lines every 1/8".
- 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!
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:
Guidelines4Quilting
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