Hello,

Sorry for the vagueness, perhaps a picture will help. Both points are on the truncated cone and the tapered helix is following the cone surface. If there was some way to pull the helix to the red point since the pitch is not known, it's a bit of a chicken/egg issue. The pitch would change along the same axis as the helix while following the parameters set for the tapered helix. I don't think a 1D scale will work since that would then have the tapered helix deviate from the truncated cone surface.