- Take a rectangular sheet of paper and fold it
into strips like an accordion. These folds are the
same as the stem fold in the leaf project.
- For best results, mark the folded strip into equal sections so you can fold your map into equal "squares."
- Starting at one end, make accordion folds all
along the paper strip. Be sure to make all the folds
parallel to each other and at an acute angle to the
edge of the strip. These folds are like the vein
fold in the leaf, but in this case, a 60-degree
angle may be a little too acute—80 or even 85
degrees will probably work better. The key is to be
careful not to make the vein folds perpendicular to
the stem fold.
- You may find the final step easier if you repeat Step 3, creasing all the accordion folds (the "veins") in the opposite direction before continuing to Step 5.
- Now unfold the whole sheet and notice that each
straight "stem" line is folded the same direction
all along its length, either as a ridge fold or a
valley fold; and each zigzag "vein" line changes
from a ridge to a valley or vice versa whenever it
crosses a stem line. In Step 6, you will reverse
this.
- Reverse the appropriate folds so that each
zigzag vein line is folded the same way across its
length and parallel vein lines alternate from ridge
to valley. At the same time, each straight stem line
should be refolded so that it changes from ridge to
valley or vice versa each time it crosses a vein
line.
One thing you will notice is that it can be difficult
to change the directions of the folds, but with
practice, you should be able to figure it out. This
difficulty points to one shortcoming of a map that's
folded this way: you can't unfold just a section of it;
you have to fold or extend all of it at once. However,
that's the reason this fold is such a good design for a
leaf or solar panel: a pull or push along a single axis
will extend or collapse the entire surface. That's a
much more efficient motion than the many different
movements required to open a surface folded
conventionally at right angles, like a standard road
map.