when I try to use any surface formula like in the image I don’t know how to use the formula to get to the final surface.

Just looking at what your shapes are, other than a surface there’s not much you can do. It looks like your trying to generate an optical illusion, which real world polygon shapes need to be closed to be created. You have a never ending helix in the left SS.

read this:

http://www.cs.mtu.edu/~shene/COURSES/cs3621/NOTES/surface/basic.html

evaluate these equations with two parameters (U and V for x,y,z for and you will get a point in space.

I think it might be more clear if it’s clear that there are 3 equations in the first list, one for each dimension (x,y,z)… then there is the domain of the parametric variables.

Once you generate points on this surface you can try building a nurbs surface by points, or drawing curves on that surface and lofting etc.

1.- **Create a range of numbers:**

u = 0…2*Pi

v = -1…1

If you want to increase the number of points use the # operator:

u = 0…2*Pi…#points

v = -1…1…#points

**2.- Use Formula node and set lacing to Cross Product or use replication Guides.**

x = first formula

y = second formula

z = third formula

**3.- Create the points with Point.ByCoordinates node.**

**4.- Manage the list.**

**5.- Create the surface.**

Use an Integer Slider, the “number of points” must be an integer. Set the Cross Product just for the formula nodes.

When linking the second formula with the y, it give my the same problem, and when I used the integer slider the number of U (7) and V ( 3 ) become very low.

You need to start the U range from a number greater than zero, otherwise the result is a self intersecting surface.

Thanks very much