Square spiral with a bias?

[design_geek_83]

Does anyone know a way to model a square helical shape which is more dense on one end than the other? I have found the spring tool which features a segment dialogue box and is able to make a basic square spiral, but unfortunately lacks the bias dialogue of the common helix command. Any suggestions would be greatly appreciated.

[Tommy L]

what do you mean by 'more dense'?

[design_geek_83]

The slope would increase as it rises. Sorry, I should have been more concise.

[alias_marks]

Not exactly sure what your getting at here... but I'll take a stab...

 

Perhaps model a spring Shape then ffd it so it tapers towards the top and apply your square as a loft along the new shape...

 

Or maybe you mean having the box get larger? Then maybe a two source loft is the best option moving from a small square to a 'more dense' square at the end?

 

Pics or a quick sketch of what your trying to do would definitely help narrow down

 

Cheers,

[design_geek_83]

Alias, thanks for the reply. The attached image is loosely what I am after, but square in profile rather than round.

[Claudio Branch]

1. Create a Helix (use Measure Utility to get it's length)

2. Create a box and change the height to match the length of the helix

3. Apply a Taper Modifier to the box and adjust Amount value to suit

4. Apply a Path Deform Modifier (WSM - World Space Modifier) to the box

5. Click on Pick Path, select the helix and then click on Move to Path.

 

Looks like a Variable Swept Helix when your done:

 

[ATTACH=CONFIG]38143[/ATTACH]

[design_geek_83]

Thanks, Claudio...like this, but square (in the other profile!)...I am trying to make it spiral around a box. That seems to be the catch, I have scoured the forums/tutorials long and hard without any luck. What I wouldn't do for a segment dialogue in the helix properties...

[Stephen Thomas]

Ok, I think I know what you're after. Following the attached image below, first create a cube with 4 height segments. Then use an edit poly modifier to join the vertices and create a single spiral. Now select these edges and create a new shape from them. Copy this shape up a few times then attach them together and weld vertices. Apply an FFD3x3 modifier and adjust the heights to suit. Grabbing the middle control points will give you the same effect as the bias control in the helix. Now just apply a sweep modifier to give it the desired cross section, et voila!

[design_geek_83]

You're the man! Thanks, Stephen.

[design_geek_83]

Works like a charm!

[Tommy L]

you may suffer rendering issues due to the faces being parabola (vertices are not in the same plane)

[design_geek_83]

you may suffer rendering issues due to the faces being parabola (vertices are not in the same plane)

 

Any suggestions if this comes up?

[Tommy L]

not really. Is this supposed to be built/manufactured or is is it just a graphic? Hopefully all your triangles fall in the right place.

[-MerlyN-]

Easier and faster way is to use the helix, apply an editable spline and just remove the vertices, you dont need.

[design_geek_83]

Tom, this is purely graphic...thankfully. Since the helix is wrapping around an object that steps back, I have had to move some vertices around and the geometry is getting a bit sloppy...although, I think it will suffice for the renderings that I will be producing.

 

Merlyn...duh, why didn't I think of that! Brilliant.

[design_geek_83]

you may suffer rendering issues due to the faces being parabola (vertices are not in the same plane)

 

Tom, I finally found a solution to this. Instead of using a sweep modifier on the spline, I opened up the rendering dialogue of the spline and enabled the “Renderable” and “Display Render Mesh” check boxes. This made the geometry very simple where I have divided the spline segments and manipulated the vertices, solving the rendering issues that you were describing.