version1
folded base
version2
add border graft(one to ten ratio)
later fold as usual following Montroll's instructions
now here's a variation from montroll's method to lock
precrease
this flap,tuck it beneath the other to lock
like this
repeat on 3 sides
top view
bottom view(underside)
release the border graft
rearrange and refold step 9to12
repeat on right
finished form.repeat on 4 sides
bottom view of 1 released border
bottom after repeating on 3 sides
expand the flap to form triangle
like this. repeat on 3sides
the 4triangles will overlap each other
sink it in
now we obtain the octahedral cross
