-
Ba
ck
Triangle
Twist
Th
open-back triangle twist
is
a slight variation
from
the
e tr
ian
gle twist. Basically, you shift the pleats over
one
pleat width,
so
instead
of
meeting together at
single
point they overlap a bit. This overlap creates
an
~n
triangular
space
. You create
new
creases
that aren't
aligned
with the grid, and these
new
creases
form the open
triangle
in
the back.
1
Fold
the
crease
li
nes
as
shown in figure 65, slightly
and
consistently off-center on a precreased triangle
grid.
Pay
close
attention
to
the
creases
you
are
creating
for
Ope
n-B
ack Square
Twist
Although
it
is
similar
to
the square twist, the open-back
square
twist employs diagonal
creases
that
don't
match
up
with the common 90- and 45-degree angles and lines
commonly
used
in
square-based tessellations.
Because
of
these
d
iff
erent angles,
an
open space
is
created on the
back
side
of
the paper opposite the twist.
Open-back square twists differ
from
regular twists
In
their inability
to
change rotational direction
without
requiring new pleats
to
be
made. You can
use
different
diagonal distances
to
change the
amount
of
rotation and
the
overall
size
of
the offset twist.
FIGURE
69
your newly formed triangle,
so
the folds accurately connect
the corners
of
your triangle together.
These
folds some-
ti
mes
are
tricky due
to
the difficult angles involved.
2
Once the
new
creases
are
in
place, collapse
the
twist
along the valley folds. Your triangle will be twisted
into
shape (figure 66).
3
Finish the open-back triangle twist by making sure the
pleats
align cleanly
with
one another (figure 67). The
back side
of
the piece should have a single triangle-shaped
hole between the pleats.
FIGURE
67
Fold slightly offset
creases
on a precreased square
grid,
as
shown in figure 68.
FIGURE
70