Intersect curves question

I’m having trouble creating a curve that passes through another curve. Every time I create the curve from points it is either straight lines ( which I do not want) or the curve does not get anywhere near the curve I wish it to intersect. Is there an easy way to accomplish this? I want to use a curve network, but the lines must be intersecting. In the image below the side curve going from left to right only intersects at its ends but not with any of the rib curves. How would I get these curves to all intersect with one another?

Hi Jeremy - try InterpCrv for this. You may need to try the different knot spacing command options to get the curve you want.


YES !!! That worked perfectly! Thank you so much.
This forum has saved me an immense amount of time and frustration. I always try to figure things out before I post here, but when I finally do post I always get a quick and succinct answer. Thank you so much for taking the time to help me over these hurdles. I sincerely appreciate your help !!!

Can you elaborate on how to use the InterpCrv feature? I have a file where I will probably have to do this hundreds if not thousands of times.

Basically this is what I am working with. The final file will have hundreds of curves in all three planes and they will need to all intersect.

intersections.3dm (60.0 KB)

And this kind of gives an idea of what the final product will look like

Hey Pascal,

This is something I have several times tried to do. Could you be more specific about how one would get a curve drawn with InterpCrv to actually go though an existing curve?

Hi Cosmas - if you are drawing point by point, the Int or Near snaps should help - if not, please post or send me an example.


Let’s say you have all the “X-curves” and are working on adding “Y-curves” (as in your file). Make a plane in the YZ CPlane and place it at the correct depth. Use the Intersect command to create points where the plane intersects all X-curves. Then with the “InterpCrv” command and the point snap on, draw a curve through all the points.

All that said - what are you trying to do with this set of curves?

Thanks Wim. I have a full size subject that was 3d scanned and I need to replicate it in 1/25 scale. The scan is too incomplete and dirty to use as-is, so I’m using it as a template to recreate it. I figured out curves from sections, but those too are too ‘dirty’, but again, they will serve as a good template for redrawing them. And since the object is symmetrical I only really need to redraw half of it. I think your suggestion will work!

That’s a bit of a job! I’m afraid, though, that you might find yourself in a dead-end street trying to use these x, y, and z sections to surface that one.

I would concentrate on getting clean y-curves and building simple surfaces from that. There appear to be quite a few flat surfaces and I don’t see why they shouldn’t be simple planar surfaces. Blends between them. Get the main body first and then add details.

It’s an interesting model for sure. I got inspired enough to have a quick search on the net and stumbled across this animation: