Drawing a spiral staircase

[raj banerjee]

Hello peeps, im trying to draw some stairs but really struggling in even finding a place to start. Basically I have a large cylinder which an access platform, I need to put some stairs to it as per the as fitted drawing which is lacking in info to say the least. I know the diameter of the tank, and the length of the stairs as the leave the platfor to the ground. I also know the floor elevation height, just not got a clue where to start.

Forgot to mention the angine of the spiral staircase in 40degrees

Any help would be most appreciated

[raj banerjee]

angine = angle

[Dadgad]

The Architectural desktop and Revit both include a Stair Tool which can create spiral stairs.
Do you have any guidelines at all?
OK we got the angle, that is a start.
What are they made of?

[ReMark]

Post all the information you have so we know what parameters you are working with. Example: tank diameter, height of tank, width and depth of stair tread, height of riser, etc.

If the spiral stairs are for a tank, unless this is a winery, they are most likely made of steel.

I'm assuming you, Raj, would tell us if you were using a program other than AutoCAD to create the stairs in.

You could work out the spacing of the stairs in 2D until you arrive at a solution that best fits what you know then take what you gain from that and create a 3D representation.

[ReMark]

3D Tank and Stairs.jpg
Is this similar to what you are attempting to create?

[BIGAL]

spiral stair.jpgA house sprial staircase its easy but only to suit a fixed template. You create a 2d/3d stair tread insert it at a point rotate it and move it vertically the only tricky bit was the spiral hand rail but this was solved pretty easy by using a rotated ucs based on 3 pts cen st pt of rail end pt of rail these must be in 3d, used to wow clients had a lisp to just splat it in place. Will try to find image. The same idea can be applied to Remarks good example.

[stevsmith]

Here's one i done earlier

http://www.cadtutor.net/forum/showth...2-Spiral-Stair

[rwhitt0724]

This is old obviously but I was searching spiral stairs. I can't generate you a 3D spiral stair but if you need one detailed, I'm your guy. lol

[JD Mather]

The Helix command will be your friend.