This command joins 3DPOLY entities into a single 3D polyline entity.
Select the 3D polyline to join: pick a 3D polyline
Select the other 3D polyline to join:
pick a 3D polyline that has a common endpoint with the first
3 segments added to the polyline.
Pulldown Menu Location: 3D Data and Edit > 3D
Polyline Utilities
Keyboard Command: join3d
Prerequisite: Plot the 3DPoly lines to use for
selection
File Names: \lsp\join3d.lsp, \lsp\poly3d.arx