This is the curve parametrized by x=tcos(t), y=tsin(t), z=t from t=0 to t=5pi. There are several versions of the curve:
1) spiral_new_merged.stl file has the equations imprinted on the curve - we think this is the best file to print.
2) spiral_thick.stl has equations on the curve, but jutting out of the curve.
3) spiral_thick_no_equations.stl is just the curve used in each print.

This model was designed and printed by my WLU summer research student Ryan McDonnell ('17).