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flible spring isn't playing ball!!!

Uni Phil

New member
I have been trying to put a flexible spring in a shock and have made it flexible which seems to work to a point.

The problem that I am having is that when the spring is compressed, instead of the pitch getting smaller, the pitch stays the same and the shock is shortened in length, making it look like its been cut off at the top so that it can fit in a smaller gap.

Is this supposed to be happening, or do I have to make the pitch variable in some way.

Any help is greatfully recieved


The term flexible doesn't really mean that Pro/E will automatically compress your parts in a realistic manner. Instead, it means that you can vary any dimension that was used to create the part. If you have a dimension that governs the spring's pitch, then you can vary that as well.

Some thought could be put into the part ahead of time by tying the pitch to the length such that only a single dimension would need to be changed to simulate the compression in the assembly.


Uni Phil

New member
Cheers for that Brian_Adkins, although I do have to find a way to vary the pitch according to the spring height.

I have a feeling that will have something to do with family tables right, and that is the one thing that i have steered from which I know is a weekness that I am going to remedy.

I'll find out how to link the pitch to the height via family tables and post something up either way.

Cheers again



A simple relation could be used to drive the pitch. For a simple example:

If the free length is 100 mm and there are 10 wire turns, you could write a relation that sets the pitch equal to the length/10.



Phil - the method Brian mentions doesn't require family tables. In fact, you could enter that relation direct from the model screen. eg:

- right-click the spring protrusion & show sketch dims

- switch dims (Info>Switch Dims)

- take a note of the overall length code (eg: d3 or whatever)

- double-click to edit the PITCH dimension

- enter d3/10 as the value

- Pro/E will ask if you want to enter this as a relation...

hope that makes sense.


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