Ellipsoid stairs?

[Anonymous]

Is there any way to design a stair that follows an ellipsoid profile as opposed to a circular one?

[Anonymous]

Yes, it could be done. But the result is somewhat impredictable (see the picture).

[Anonymous]

Thanks andro55; I believe that you used multiple circular stairs. I was looking at something more straightforward like a single stair having an ellipsoidal path. Regards.

[TMA_80]

have you tried a custom stair creation ( maybe that's what andro55 have done )
have a look in thearchicad help

ArchiStair ( Cigraph ) or Stairbuilder ( Cadimage) would be other options to consider...

At a last resort, built it manually... though, not a parametric solution

[Anonymous]

NO.
I used only a Fill for stairs outline and multi segment Arc for the line of travel.
You must use menu Design > Create Stair Using Selection!!

[TMA_80]

That's what I meant by custom stair...

[Karl Ottenstein]

I got slightly better results with the Create Stair Using Selection, perhaps because I offset the first ellipsoidal segment to make the stairs the same width, and also to define the line of travel.

Still, as you can see here and in the next post with 3D, one tread is smaller than the others and the hand rail is odd at that same point.

The ArchiCAD custom stair has no features for subsequent editing / correction - no hotspots in 2d or 3d. ArchiStair 2, on the other hand, has hotspots on every single tread, allowing you to fine-tune how you want everything built. (The initial appearance of the treads for this same ellipse was a little weird for me - but the hotspots let me correct things.)

Karl

[Karl Ottenstein]

Here's the 3D from ArchiCAD...

[Anonymous]

Thanks andro55, TMA_80 and Karl. I think I will also look at Cadimage to see if they provide a parametric solution.

[Anonymous]

Hi,

I tried following the Help instructions on Creating Stair from Selection and I just got an error that says: "Cannot generate stair with this line of travel."

I did offset the arc from the side of the fill to serve as my Line of Travel and got this message.

When I tried to use a straight line as Line of Travel it seemed to work. However, I want a curved path similar to what you've shown in your screenshots. I'm currently using AC15 (unboxed 16 but haven't properly migrated yet).

Is there something I'm doing wrong? A setting perhaps? Hope somebody can help me out.