I am currently creating a SPINAL BEND feature in Wildfire 5.0. I am able to make the spinal bend with no trouble whatsoever. But I do have a question about the resulting geometry.
It seems that the spinal bend sketch can alter the final length of the spinal "bent" feature so that it is longer or shorter than the original. I want the "center" or "neutral axis" to be the same length as the original, but the length of the resulting spinal "bent" feature somewhat complicated to calculate...especially if I have many different curves in the spinal bend sketch. How do I constrain the spinal bend so that the "neutral axis" is the same length as the original feature (i.e. prior to the spinal bend).
Easiest way is to go into the sketch for the bend curve, add a ref dimension on the length of the original geometry, and use a perimeter length dimension on the spinal bend curve controlled by a relation. You have to make sure you get the correct original length when doing the ref dimension (or, "known" dimension as it will actually show up as). Works great, and easy. sometimes you might have to create an evaluate feature and use a relation controlled by that, but you should be able to do it easily as mentioned above.
I have some spinal bend parts in my photo album here for reference.
Good luck, and if this helps please remember to mark it answered.
In Creo 3, there is the option to maintain the geometry.
I end up doing some work using clocking angles in Cartesian sketches. I just use a variable that covers the overall I want from the bend's spine. If you are mapping to a cylinder, the length is pi*D and pi*d/360 cover each degree along the length. If you are mapping to a contoured curve, then you can use this same information as a ratio along the curve.
This really makes it a dimensionless problem. If the bent feature sketch is robust enough, it should tolerate a wide range. Of course, this is similar to let the system just stretch your feature onto the spine unless you need true circles and arcs. The position of that spine in relation to the unbent part is all important. This determines where the required deformation takes place. You can use the K or Y factor formulas to "accurately" determine the developed length in relation to the material.
If it's a quilt/surface, then even better.