Custom Staircase

[cwailes]

How do you create a custom staircase like this one? I Know the radius for the two curved sections and I can pretty much create the staircase. However, the part I can't figure out how to make is the bottom portion that curves out and back in. Do I have to model that in 3D or is there another way?

[CipesDesign]

You *might* be able to get close to this configuration by using a different "flight" for each of the different width steps, but I doubt you can get the curved parts to be curved.

I would approach this as a 3d modeling task. It would not be particularly difficult to build out of extrudes (and perhaps other 3d objects) however it would require a re-do if/when design changes were made.

[cwailes]

Thanks Peter. I thought it would probably be a 3D modeling task. However, I will give your idea a try and see what I come up with. Should be a lot of fun.

[Jeffrey W Ouellette]

Chris,

You could start by using the Stair PIO and getting as close as you can and then either ungroup the whole thing an customize the bottom treads from there, OR you could use the Stair PIO for everything but the bottom treads and model those separately, as Peter suggests.

[brudgers]

I agree with Peter, model it.

I'd probably start with the stair profile (side elevation) as an extrude and intersect it with a tall extrude of the plan view.

[bcd]

I'd draw in 2d plan, keeping the tread going constant along the centerline.

extrude each tread by it's thickness

Set bottom z height to suit or better yet set the first and top step z-height

then in front view Model>Align Distribute.

[brudgers]

Here's how I would model this sort of stair.

You can fairly easily modify the solids for the stair profile and the plan view.

[bcd]

the steps on the upper curve need to radiate from its center

[brudgers]

the steps on the upper curve need to radiate from its center

the profile may be wrong too.

It's a demonstration of the modeling technique.

So draw the 2d plan view.

Compose it as as a polygon.

Copy it to the clipboard

Edit the solid intersection.

Edit the topview solid extrude.

Paste the new polygon from the clipboard.

Delete the old polygon.

Exit editing the extrude.

Exit editing the solid intersection.

[Jonathan Pickup]

combine this with floor objects to create the radius stairs

[bcd]

Except floors cannot have varying thicknesses?

It seems that producing a max. width stairs composed of 2 flights : straight & circular. Ungrouping and editing along the lines brudgers recommends would produce the result easily.

Edited December 2, 2009 by bcd

[Kool Aid]

Here's how I would model this sort of stair.

Now, pay attention, brudgers: your stair has little to do with the requirement.

The ?side view? approach is totally wrong.

[brudgers]

stair with two subtractions

[bcd]

perfect !

[brudgers]

perfect !

Not quite.

A solid intersection would be cleaner - two objects v. three.

But the 3d engine in 2008 won't handle the complexity.

Maybe parasolids and the root-n-toot-n new stair can.