Make Accurate
Triangle Squares
Any Size!
No Fractions or Trimming
Choose a whole-number
finished size on your ruler.
The exact seam allowance
is automatically added
-
9-Patch Blocks:
1″ HSTs make a 3″ block - 2″ HSTs make a 6″ block
- 3″ HSTs make a 9″ block
- 16-Patch Blocks:
- 1″ HSTs make a 4″ block
- 2″ HSTs make an 8″ block
- 3″ HSTs make a 12″ block
Tool You Need
Half Square Triangle
Seam Allowance Addition
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Step 1:
Attach the H Addition(s)
Made of unbreakable polycarbonate
Left-handed Friendly
The 12″ Addition attaches firmly
with premium suction cups
featuring easy-release tabs.
Get two for your 24″ ruler.
(Rulers Not Included)
Step 2:
Choose the whole number.
The example shows the 3" line:
Step 3:
Line up with the selected
whole number to cut
strips and squares.
Standard quilt rulers are marked in ⅛″ increments, forcing quilters to add ⅞″, which is nearly 1/32″ too much. That excess has to be trimmed away.
No Trimming
The H Addition automatically adds the exact 0.854″ seam allowance.
Your triangle squares will
match your squares perfectly.
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.
Trim the triangle points accurately.
Cut the center square
the same size as
the trimmed HSTs
Don't have a point trimmer?
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
Sew an Accurate 1/4" Seam.
Super Easy
Seam Guide Setter
Sew accurate ¼" seams:
The secret to sewing accurately
is a Scant ¼" seam allowance.
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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