How can I wrap a helix up a funnel?

[greatson]

Hello Sketchucation forum!

Essentially I need to wrap a helix line up the side of this funnel, so I can use that contour to create a spiral staircase from the bottom to the top. I'm now at the point where I'm lost in the library of extensions I've installed trying to achieve this, and cant seem to figure it out from the youtube tutorials, so I'm reaching out to the community!

I would very much appreciate if anyone could help me out with this. Also Very open to any tips on the right extensions. The shape of the stairs will have to change as they go up as the overhang becomes more flat on the top of the funnel.

thank you for any suggestions!

-grevoir

---

[JQL]

I think you could solve it using native tools.

Design the spiral you want and use "intersect faces" with geometry to find where the spiral intersects the shape you have.

[JQL]

Brilliant!

EDIT:

It works with any vertical surface of any shape?

EDIT2:

I was going to post this, then I quit, then I came back:

---

---

Helicoidal Stair.skp

[sdmitch]

@greatson said:

I need to wrap a helix line up the side of this funnel, so I can use that contour to create a spiral staircase from the bottom to the top.
-grevoir

Center funnel on the model origin then execute plugin. Pitch is the vertical distance between start and finish of each turn.

---

helix on surface.rb

---

[greatson]

@sdmitch said:

@greatson said:

I need to wrap a helix line up the side of this funnel, so I can use that contour to create a spiral staircase from the bottom to the top.
-grevoir

Center funnel on the model origin then execute plugin. Pitch is the vertical distance between start and finish of each turn.

Hey Mitch! thanks for replying, I'm trying to get the plugin to work, but when I execute it nothing happens. Any ideas on what I could be doing wrong?

-gr

---

helix surface try.mov

[sdmitch]

@greatson said:

Hey Mitch! thanks for replying, I'm trying to get the plugin to work, but when I execute it nothing happens. Any ideas on what I could be doing wrong?

-gr

Yes, you need to move the funnel down to the XY plane. The plugin starts from the Model ORIGIN and doesn't find a surface because your funnel is "up in the air".

[sdmitch]

@pilou said:

Does this normal ?

[attachment=1:txalgjqz]<!-- ia1 -->projected.jpg<!-- ia1 -->[/attachment:txalgjqz]

Yes, because plugin, as presently written, assumes a symmetrical cylindrical object.

[pilou]

Put the form on the origine!

Else does this normal ?

---

projected.skp