snail model

 From:  Grendel
2013.5 
I made one spiral with a large circle(c1) at the left and a smaller one at the right(c2). I then snapped a smaller spiral to the end of the first and made a small circle(c3) at the end of that. I then swept C1 & c2 along the big spiral. Then swept c2 & c3 along the small spiral.