Spring has no centerline

[mcian14]

I created a spring but when I try to assemble it with constraints it appears to lack a centerline. Any ideas?
Autodesk Inventor 2012 

[trumpy81]

I have encountered the same problem. Also the spring ends are NOT flat even though I select that option. Anyhow I do a revolve to flatten the ends and then do a small but rough bore down the center of the spring. That gives me a D shaped wire but I can use it to constrain the center of the spring.

HTH

Regards

Andy M

[mcian14]

could you explain a little further how you go about doing this? I am somewhat new to the program

[trumpy81]

First, select a plane that goes through the center of the spring vertically and make a sketch on that plane. Next, draw a rectangle from the center of the spring that intersects the end of the springs coil (the wire) at it's midpoint. Make sure you draw a vertical line or construction line through the center from top to bottom, this will be the axis for the revolve operation. close the sketch and use revolve to cut through the coil ends, top and bottom.

Once that is done, draw a sketch using the top or bottom flat part of the spring as the plane to draw on. Draw a circle in the center of the spring that is just slightly bigger than the inner diameter of the spring. Once that is done, use extrude to cut that circle through the center of the spring.

If done correctly, you can now constrain the center of the spring.

If you need any more help, just holler. 🙂

[mcian14]

thanks! I did it in a rather sloppy way before reading this but I got it to work! 
I can feel my brain growing!

[blair]

You can use the Origin Planes of the spring, if you are using a spring from the Design Assistant within Inventor

[JDMather]

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@mcian14 wrote:

thanks! I did it in a rather sloppy way before reading this but I got it to work! 
I can feel my brain growing!

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Attach your file here.

Use the origin axis as the centerline as suggested by blair and getting flat turns should not be a problem.

[trumpy81]

I should have added that my technique is for springs drawn using the 'coil' command. For some reason, that I have long forgotten, I never used the Design Assistant for springs, gears yes but not springs.

Anyhow, I just tried it in 2013 Pro and they work great!! And they do have proper flat ends etc... perfect! ... lol

Thanks for the hints guys.

[7997redtail]

I think i have found another solution.  I have attached a word doc that has two screen captures showing the difference between a :mate" and a "insert" constraint option and the selection options that come with them.

The text from the word Doc is below in case the attachment doesn't show up.

In this screen capture the Constraint option “insert” is being used.  With this option you can’t use the X,Y and Z options.   You can’t see the mouse on the Y axis but it’s there and no red axis line is indicated on the spring.

In the next screen capture I used the Constraint option “Mate”.  With this option you can use the X,Y and Z options.  You can’t see the mouse on the Y axis but it’s there.  Look closely and you can see the red axis line is indicated on the spring.