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creating 3D curves


New member
What you are referring to is the infamous 2 projection
curve. Never use it.

Do this instead. Extrude a surface from a plane as you normally.
Then Extrude another surface from an adjacent plane. Where they
meet creates an intersection. This is much easier to visualize and allows
a trail for others to follow.

Edited by: design-engine


New member

i am trying to sweep along a trajectory,which is a 3d curve.

if i am trying to do as u say i am getting surfaces also .i dont want surfaces.

can u explain me like that.

and one more thing is can u tell me which concepts should i know toroughly to get grip in pro/engineer wild fire



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u can merge 2 ( 2d curves) by highlighting one

->edit ->intersect-> select the 2nd curve.

have a play with it you'll work it out fast.

but really there are many ways of making 3d curves. maybe you shoudl
tell us where its going possible show us a picture of what your doing.


New member
You can also use design-engine's method of creating intersecting
surfaces, then select both surfaces and "Edit -> Intersect."
You'll get a curve at the intersection.

I didn't realize that the projected curve was a bad thing, so this
method might be bad, too. Design-Engine, can you comment?


New member
When I learned the 2 projectioncurve methodI felt like the veil had been lifted and I could take on the world!

And now I find out that I might be wrong... My faith is weakening... Please tell me why Design_Engine? I'm begging you.

How do you hide the generated surfaces without also hiding the curve? I can see why it might be a little easier to visualize, but I need more...


New member
I agree with Design-Engine. It is much easier to identify the two created surfaces than it is to figure out the 2 sketches used to make the intersected datum curve. If you do not like the surfaces, put them on a layer and blank them. Either way gets you the same result. Using the surfaces, makes it easier for a future user to identify how the feature was created.


New member
So if you were making a sweep trajectory or surface boundary and needed
a projected curve, what would you do? Create surfaces, then Edit
-> Intersect?


New member
Info, Parent / Child?

I don't see any problem either way. Coming from a system that didn't have the intersect curve function I'm kinda tickled it's there; saves a lot of steps.


New member
Project onto a surface is fine. I just explained the two surfaces
merge thing because one can fully visualize the resulting curve.


New member
so is it better to create 2 intersecting surfaces then merge them and
use the merge edge as, say, a sweep trajectory, or is it better to
create the 2 surfaces then intersect them and use the resulting curve
feature as, say, a sweep trajectory?


New member
If you understand corect how stuff working is not difficult tu use

Only problem i see here is to build the two curves

Is true, is better to looking with two surface,and easyly to understand

But if you want to create a curves from two projection already made is not wirking always



New member
Does anybody know if it is possible to use the edit intersect command with a curve created in ISDX and a normal sketch? or if there is another way to do it?


New member
The isdx and sketch do not intersect. I would imagine an extruded surface and an intersect at that point would work.

As far as my .02...I never extrude two surfaces to get an intersection, instead opting for the 2 curve approach. I can't stand trying to layer every little thing off...it's too time consuming and I can't think of that many unique layer names. Surfs that are close to one another or are very close in intent are way too hard to differentiate in my opinion. Dealing with all the extra unnecessary surfaces is a waste of time as well in a resolve situation. U..G..L..Y! Besides WF will automatically hide the sketches.My models are much less cluged by not having so many construction surfs.(sounds like the old days of Catia and UG).I add feature names where it makes sense to point subsequent moders in the right direction.

You will help the next person by keeping the model clean of extra crap more than having every step mapped out graphically IMHO.