About aligning a 2D section normal to a line

Hi...

I have a 3D curve (spline, not aligned to the principal axes) and a 2D section of a tunnel...what I need to do is to align this 2D section to the curve (from its longitudinal axis in the first section of the curve)... How can I do this?

Hope this is enough to explain what I am trying to do.

i attached an example of the problem ( http://we.tl/MPhaWL7W8O )

Thank you

The vector from the end of the spline (the first CV - Control Vertex) to the second CV defines the slope (and the radius of curvature) at the start of the spline. Use these two points and the 3DALIGN or UCS ZA command to position and orient the 2D section. I do not know how to use OSNAP to snap to a CV point so I would use the LIST command to get the CV coordinates (listed as Control Points). To see the CV points select the spline and change the CV frame paramter from Hide to Show or use SPLINEDIT

Why is the file size of your drawing with just 10 objects so large (6MB)?

~Lee

The vector from the end of the spline (the first CV - Control Vertex) to the second CV defines the slope (and the radius of curvature) at the start of the spline. Use these two points and the 3DALIGN or UCS ZA command to position and orient the 2D section. I do not know how to use OSNAP to snap to a CV point so I would use the LIST command to get the CV coordinates (listed as Control Points). To see the CV points select the spline and change the CV frame paramter from Hide to Show or use SPLINEDIT

 

Why is the file size of your drawing with just 10 objects so large (6MB)?

~Lee

Hi Lee thanks for yor reply.

I was thinking that maybe if I extrude the central part of the 2d section (the empty-inner part) I would be able to use the snaps to align it with the first points of the curve... I am tryin' it now.

And yes, I don't know why this file is so big... yesterday I were like 20 minutes purging and looking an answer to it, I did not find it, so that's why I use wetransfer.

Saludos!

You should not need to do an extrude to orient the 2D section. Create a line from the first to the second CV points points of the spline (in fact, you could use OSNAP Nearest to define a second point that would yield a line close to being tangent to the spline). The add another line from the base point of the 2D section to a a point perpendicular to the section.

Now give the 3dalign command with the following input:

Select objects:

Specify source plane and orientation ...

Specify base point or [Copy]:

Specify second point or [Continue] :

Specify third point or [Continue] :

Specify destination plane and orientation ...

Specify first destination point:

Specify second destination point or [eXit] :

Specify third destination point or [eXit] :

~Lee