Modelling Curved Staircase in Autocad

[nicolas]

Hi,

 

I am working on modeling and rendering of a residential house when I came across a curved staircase and really I have lots of difficulty to model the sides and soffit of the staircase especially that there is a curve involved and everything seems to be non-planar be it side and soffit to the excepton of the landing, threads and riser.

 

The floor to floor height is 3125 including a floor slab of 125mm. The Waist is 150 mm.

 

Thanks you in advance for your input and advice.

 

I have attached a dwg and jpeg of the staircase.

Curved Staircase 3D.dwg

[ReMark]

How are the stairs supported?

[nicolas]

Here I have used surface due to the difficulty encountered. The stair is a RC Stair supported by a footing at foundation level, one side is next to the wall (left side) and the last step is the first floor slab and further supported by a beam here not shown.

[ReMark]

I think you'd have an easier time of it if you used a solid instead of a surface. If you were designing the body of a car then I could see you using surfaces.

 

This topic has been covered before. Did you look at any of the Similar Threads listed below?

[nicolas]

Hi,

 

I have been able to do much of the staircase with solid instead of surface. However the process is lenghty (many hours) and tiredsome having to position the ucs twice for each step, to loft and substract the loft geometry from te overall staircase once for each step. Even then, I am still unable to do the curved sides and soffit of the staircase. In additing, there is a railling to add on top of that. Do you have any idea what can be done to draw the 150 mm. waist and soffit?

 

 

 

Thanks in advance.

[ReMark]

pearstairs: First you have to design the curved staircase before you can fabricate it. Nicolas was trying to design his as a 3D model. Can you explain to him or anyone else attempting to do the same thing what the technique for doing this in AutoCAD would be?

 

Edit: Remark, the spamer and his post are now gone f700es

Edited December 16, 2013 by f700es

[BIGAL]

I did a spiral stair case yeras ago with a lisp just went splat and all done. The easiest way is to make 1 single stair tread section in full 3d and just copy rotate and raise the tread height. The individual 3d hand rail is made by using the UCS and 3 points that represent the +/- 1/2 rise and the 0 level centre of radius you can the draw an arc extrude a handrail and return back to UCS "world" with it basically being a spiral rail. I am sure you could now though use the helix option to do the same thing.

[ReMark]

If nicolas wants to trim away the excess solid mass beneath his stairs then the best way to do that would be by sweeping a line along the helix he used to create the stairs and use it to slice away the portion below. I think JDM demonstrated this technique in another thread.

[f700es]

Here's what I did.

 

I used the presspull command to make each step.

 

After all the steps were made I union-ed them together.

 

Then I used your original drawing and extended the step curves to make a larger solid to subtract from.

 

I used these curves and the loft command to make a curved solid to use to subtract from my stair solid.

 

I then aligned the 2 solids back up on top of the 2D lines.

 

I then subtracted the lower from the upper.

 

Took me about 45 minutes total in AutoCAD 2013.

Edited December 17, 2013 by f700es

[ReMark]

45 minutes? Did you fall asleep for 35 of them? LoL! Of course I'm kidding. Nice solution.

[f700es]

Yeah a bit of trial and error involved of course

[ReMark]

My approach is more like trial BY error!

[nicolas]

Hi,

 

Thanks. I was unaware that the thread did continue. Thanks for the additional info and technique. Will try it today and will let you know how it works out. I believe this solution is best contrary to mine which took me hours.