concentric spiral

[info]

Hello,

I need to draw a concentric spiral in Autocad 2014 to develop a fanhousing similar to the one in attachment.
Does anybody have any tips in how to do this.

I have tried to join tan tan tan circles, but the curve isn't smooth.
I have tried spiral, but this is centric.

Thx

Kelly

[Kent1Cooper · Accepted solution]

---

@info wrote:

.... 

I need to draw a concentric spiral in Autocad 2014 to develop a fanhousing similar to the one in attachment.
Does anybody have any tips in how to do this.

....

---

You may be able to use one of the commands in the attached that I did a few years ago.  It's not quite clear to me from your photo whether the equal or arithmetic or geometric spiral would be best, but try them out.  Use a large number of segments per turn for a smoother result.

[info]

Hey,

Thanx for your reply. Unfortunately it didn't help me with my drawing.
I tried all your commands but I ended up just connecting arcs.
I had to recreate that exact object, and had to measure it up completely...

I didn't give up en ended up with a great result!

greetz

Kelly

[GrantsPirate]

Helix or Spiral should work, specify two different radii, specify number of turns as .75, or what ever works for you.