I am trying to sweep anything over a spiral with a twist so it looks like a rope. Tried everything! Is there a way to do this?

For example, the equation for the spiral can be this (radians):

xt = 2*cos(t)*sin(t*0.005/Pi)

yt = 2*sin(t)*sin(t*0.005/Pi)

zt = 2*cos(t*0.005/Pi)

t1 = 60*Pi

t2 = 120*Pi