★How to make two spiral helix curves tangent at the intersection point

Issue: 

Create 2 spiral helix curves with different pitches, but they do not touch at the intersection point (as shown in the figure below). How should this be solved?

Solution:

1. Click Wireframe → Concatenate, select the 2 spiral helix curves, and set G1(Tangent) as the Continuity. Then set Global as the Method to make it smooth.
   Note: This command will slightly modify the shapes at the intersection point of the 2 spiral helix curves.
   
2. In this way, 2 spiral helix curves will merge into 1 curve with continuous tangency.
   

★How to make two spiral helix curves tangent at the intersection point：https://confluence.zwcad.com/pages/viewpage.action?pageId=337406229