Hello,

Thinking this through you won't be centered on axis if you just want to make one revolution, correct?

Hi Gunter,

I am uncertain what you are trying to do. What do you mean by center? Lines connected where and to what, and orientation?

Using Burr's 3 pt method (with a circle), I got this .3dm

- Brian

Okay, after more thought, I'll use a tootsie roll analogy.
Place a helix around a short cylinder, with the desired number of turns, x.xxxx.

Place a line segment on each end, from the center axis outward.

Connect each helix end to one of these line segments, with another curve.
suggest MoI tapered helix command, or maybe variable pitch helix script, _VarPitchHelix.

- Brian

Or just use the tapered helix?

Hi Gunter,
In the first video, I used the rotate by axis command to rotate "around your lines", and the created arc to get a center point for aligning the helix's center vertically with the lines. (Rotating the helix and leaving the lines stationary)

Here's another way where I use the edit frames rotation abilities and just rotate the entire geometry set so the lines are at the "12 o'clock" position (Aligned).... I also use "BoundingBoxCenter" instead of drawing the 3 pt. arc to get the center of the helix.

Hi Gunter,

"""""""""""I watched your video but couldn't figure out how you got that spiral to join the vertical lines in the first place ?""""""""""""""""""

I see. I misunderstood this before.

I just did that on "Your file". I didn't create the lines and helix. Just did the alignment I thought was the question you were asking....

Burrman,

Thanks ever so much for taking the time to make and explain the video.

Unfortunately, from what I can tell the centre of the spiral is still to one side of the two vertical lines. In other words the centre of the spiral is not inline with the two lines. I'm looking for it to be in the centre while still connecting to them.

Am I just not getting it?

Sorry and thanks!
Gunter

Hi gunter,
No, you missed it. In the first video i moved the center of the spiral to be in line with the lines. In the second video i rotated the lines to be in line with the center of the spiral.

Unless i misunderstood what what you mean by "in line"?

Others seem to be responding reading your request as "starting and ending the spiral at the poles"????? A spiraled sphere?

Just read your response in another thread and it appears i misread what you were looking for. The spherical spiral starting and ending at poles.

Anyway....

there was a "spherical spiral" command written. I attached it here. I don't remember who wrote it for credit...

Hi Burrman,

Many thanks for this and I'm happy it's resolved.

Thank you for your help!

Gunter