2d sketch spiral

[Lawrence]

Good morning.
I would like to create a spiral on a 2d sketch, and then use it as a guide to serialize a hole.
How can I create this spiral?
I came to mind that you can use the "Equation curve" command, but in almost 20 years of using inventor I had never happened to use it and I can't figure out how to set values in options.
Can you help me?
thanks in advance

 

[Peppe]

I think of the 3d sketch, helical curve and in definition spiral selections

 

[Lawrence]

I think of the 3d sketch, helical curve and in definition spiral selections
View attachment 65655

Thank you. @peppe, but I even tried without going out.

 

[Cast16]

Thank you. @peppe, but I even tried without going out.

as he said @peppe:

 

[Lawrence]

as he said @peppe: View attachment 65656

first I apologize @peppe.
I was definitely wrong!
second thing: @ cast16 Can you explain how you did it? ?
That's what I want to do.

 

[Catafratto]

using the equation curve (polar mode):

 

[Cast16]

Can you explain how you did it? ?
That's what I want to do.

I made a video. I hope it is clear:

https://autode.sk/3lidsub

 

[Lawrence]

Thank you very much @catcher to the @ cast16: I tried both methods and managed in the company!
sometimes the simplest things are the ones that are used less...

Good continuation!