# Creating a circular NURBS surface

Hi all. I’m trying to obtain a circular surface with a radius 0.5 m. To obtain that, I have drawn a circle and then trimmed the circle to obtain four quarter arcs. Then, I have used the button of Surface from network of curves by selecting the four quarter arcs. It gave me a circular surface. However, it is not exacty a circular surface. When I have drawn a line from the center to the circumference, the length of the line changes as 0.49 to 0.51 which is not 0.5 and I understand that it is not exactly a circular NURBS surface.

How do you obtain a circular NURBS surface ?

Best Regards,
Ahmet

create a 0.5m circle, select it , go to the surface drop-down menu and select surface from planar curves

Maybe draw a line whose length is the circle radius and then use Revolve about one endpoint?
(if you are looking for a surface with a circular NURBS structure)

Otherwise, drawing a circle and using PlanarSrf as Tone suggests above is the way.

Hi @kahasim
Could this be a tolerance thing? I just tried the same thing, and the radius stays 0.5 as expected. What are your tolerance settings?
-Jakob

Thank you Mr. Normand. I have increased the tolerance and it solves the problem. Have a safe and good day.

1 Like

Thank you Mr. Helvetosaur. I have learned a new way to obtain a circular NURBS surface with your suggestion. Have a safe and good day.

Thank you Mr. Tone for your suggestion. When I have increased the tolerance, it has solved my problem. Have a good and safe day.