3D spiral- how to make?

Hi everyone.
How can I make a 3D spiral? I need it for the balustrade of a 3D
spiral stairway, so it must be "round". I hope you understand what I
mean.
Thanks in advance!
Reply to
SPAMERS_the-trooper
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That's no fun!
Reply to
The-Trooper
One way to draw a 3D spiral with out a program is to use spline or the 3dpline and polar coordinate point entry ( distance < angle, Z)
To make this easy you would do this off a User defined UCS origin distance being the radius of the spiral angle being the angle of incrimination about a circle. Z being the rise per angular step.
for a simple example a spiral a 6 unit rad and 6 segments about a circle and a 1 1/2 unit rise per rotation would enter as
spline 6,0,0 ( start point) 6
Reply to
David Harper
And if that looks too much like hard work use Excel to calculate each point and save the results as a script file.
Terry
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Reply to
Terry Rawkins
Terry is correct. I have Some cad training using a book by John E. Wilson and the book says the same thing.
To male it even easier go to
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and search for 'spiral' and there is a 3Dspiral program
Reply to
David Harper
I'm using AutoCAD 2002 in witch command 3Dpline does not exist, and like You said, neither extrude nor tabsurf works with spline. So it looks like the only way is lots of UCSistems, many arcs and extrusions. Unless You have any other idea.
Reply to
The-Trooper
"3dpoly"
Reply to
Larry Travis
Yes, but I can't force it to go through the points when spline curve is used (in pedit).
Reply to
The-Trooper
Sorry, just meant to say the command is "3dpoly" and not "3dpline", whether or not it works for your application. I just found a link that may or may not help you, but will give it to you anyway because I think it does the best job describing how to model something that is fundamentally a 3d spiral. It is an in-depth tutorial on modeling a 3d screw, but perhaps you can apply the concepts to your stairway.
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Good luck, LT
Reply to
Larry Travis

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