>>Get 20 spheres of styrofoam or something similar, and paste them together, into four pieces, like this:
>
>Hilmar,
>
>Is this it?
>
>1 long, 2 short on the bottom
>1 long verticle in the center
>2 short across
>
>Renoir

place 2 short ones at right angles to each other

    0 0
  0  0  0
    0 0
  0  0  0
    0 0

(difficult to draw)

long ones go down centres of short ones

short ones are in middle, long ones outer most

I'll take Hilmar's advice & make it for my children