Welcome to 3DCADForums

Join our CAD community forums where over 25,000 users interact to solve day to day problems and share ideas. We encourage you to visit, invite you to participate and look forward to your input and opinions. Acrobat 3D, AutoCAD, Catia, Inventor, IronCAD, Creo, Pro/ENGINEER, Solid Edge, SolidWorks, and others.

Register Log in

How to model an arc coil spring?


New member
This is my first post to the site. I was wondering how you would model an arc coil spring. There must be a formula I can use under the functional spline form under algebraic equation pick. Then I could do a sweep of a cross section to create the spring but I need help with the equation or a better idea.
I'm always using the Helix Function..( Insert-Curve-Helix).

With this function you can state the Nr of Turns, Pitch.
You can either choose to use a radius or a Law (start diameter, end Diameter)
Also you can define a right hand or left hand helix....

After you've constructed the Helix just use the Tube function...(Insert-Sweep-Tube) to make the actual spring.

Good luck...
Last edited:


New member
Here is the formula for a function spline The created a Garter type spring.

I use this in I-Deas I do not know how much different it will be to use in UG NX software.

r1 = 100
r2 = 25
q0 = 0
q1 = (2*pi)*u+q0
q2 = 60*q1
x0 = 0
y0 = 0
z0 = 0
x1 = r1*cos(q1)
y1 = r1*sin(q1)
z1 = 8*u
x = x0+x1+r2*cos(q2)*cos(q1)
y = y0+y1+r2*cos(q2)*sin(q1)
z = z0+r2*sin(q2)

r1 = large radius of the torus
r2 = radius of the helix around the torus
q0 = initial angle of rotation of the path
x0,y0,z0 = centerpoint of the torus


New member
I do believe U=1 1 Would equal 360 Degrees

So .5 would be 180 and so on. It is how much of the garter spring you want. If you want a full circle U=1