Ok ! its solved With Your hint to "put 2 collinear vertices on each side " .
Thank You Fredo . Your plugins is excellent .

Thanks for your video fredo . but your video is not my issue .
please select all edges and run "smooth contours " . Certainly i can select only A Points Too but My issue is "smooth by section" in "smooth contours "tool Does not work .

Hi Again fredo and thanks for your Answer.

I uplode sample file . please look at it . in this file I showed points with A and B .
I would like to action fo "smooth contours " work On A point and Donot Work On B Points .

thanks from you in advance

Curvizard problem.skp

Hi again
No answer for me ?

Hi Fredo
Thanks for your principal And Amazing Plugins .
I have problem with smooth contours option in Curvizard . its not excluded sharp corner from smoothing .it means "smooth by section " and "Smooth Collinear Edges " not working for me. please see video on link if I could not Explain it . thanks .
https://www.mediafire.com/file/a8v93r6yrc43gx0/Curvizard.mp4

I found this option of profile builder . thanks JQL .

@jql said:

The best one is Profile Builder 2, though it's not free.

Hi JQL thanks for your reply .

Profile Builder 2 have tool for copy along path ?! can you give me Introduction movie or Tutrial Link? I think Profile Builder have demo version.

@pilou said:

Look at Path Copy & Path Copy Pro by Rick Wilson
http://www.smustard.com/scripts/

You can also use CuviLoft by Fredo6 for have a segment perpendicular to a path!

[attachment=1:3anw72bh]<!-- ia1 -->GIF_curvi11.gif<!-- ia1 -->[/attachment:3anw72bh]

Components Stringer by Chris Fullmer can also make something!

[attachment=0:3anw72bh]<!-- ia0 -->GIF_comp.gif<!-- ia0 -->[/attachment:3anw72bh]

In general all these works with the "nodes" & "extremities" of segments of the path
so drawing it in thinking of that!
Beziers by Fredo6 can help for this!

Hi pilou . component_stringer Is dead and not worked in Su 15 and 16 .

Curviloft can not copy along path .

Hi

I have problem to choice a one tool for copy alond path in SU .I DO THIS WORK IN CINEMA4D very easy with cloner and result was good .which tool or extention in su can do this work ?

@box said:

The component axis for your column component is way of in the distance.
Right click on one of them and Change Axes and the flickering will go away.
The normal Z-Fighting will remain where faces try to occupy the same space.

Hi Box . THanks , Its solved !
Thanks for your reply. Place of Axes is important and I forget its .

thanks again and again .