How to make an edge perpendicular to the other edge? Or, parallel to the other edge?

Support Modeling
#1

Hello, I have a problem in Blender 2.63.:confused:

In EDIT mode, there are two edges in mesh，A and B,
they are different length and different angles pose.
I want to make an edge perpendicular to the other edge, like “T”;
Or want to make an edge parallel to the other edge, like “=”;
How to do it?

only I know is, I can rotate an edge itself 90 degree in normal orientation,
so, if I have “T”, I can get “=” .
But how to get these two edges become “T” or “=”?

I use Snap – Closest, just can move two edges on the same vertex place, like “V”,
and then I rotate one edge (Snap – Closest, Pivot Point at bottom vertex of “V” ),
but two edge can not coincide, just very nearly, but not paralle, not coincide.

Sorry my poor English, thanks for your help.

btw:
If Blender’s snap tool can work like AutoCAD,
for example: snap perpendicular, snap the point of intersection,
snap sphere center, snap sphere tangent point…
the job will be done more easy.

#2

To create a perpendicular edge you duplicate and rotate by 90°. For a parallel edge you duplicate and move/grab for positioning. Try playing around with different pivot points.

#3

I found a way to solved this problem, please see the picture I draw:

(1)
Snap vertex closest
Move edge A to the end of edge B
(2)
Select edge B
Set orientation as normal
And create a new orientation named edge-B
(3)
Set select mode as Vertex
Select a vertex Snap cursor to active vertex
Set pivot point as 3D Cursor
And Orientations still using edge-B
(4)
select edge Aand rotate it: R Z Z
We can see edge B lying on the Z-axis
So,
want to let edge A parallel to edge B, it must 2 steps:
R X X snap vertex closest
R Y Y snap vertex closest
Now
edge A complete lying on the Z-axis, too.
so, edge A parallel to edge B

And then…if (Orientations still using edge-B)

G
Move edge A anywhere
edge A still parallel to edge B

R X X 90
or
R Y Y 90
can make edge A perpendicular to edge B

perpendicular_to_edge.jpg411×2300 142 KB

#4

How about this:

Determine exact length of Edge B (Under ‘Mesh Display’ check ‘Edge Length’ checkbox in properties panel for Blender to display length)

In edge mode, create custom orientation based on Edge A (select Edge A and hit Ctrl+Alt+Spacebar)

Extrude edge A (the exact length of Edge B using numeric/keyboard input) into a perfectly rectangular plane (90 degree angles at all verts) using the custom orientation along one of the two axes perpendicular to the edge. Probably either ‘E X X’ or ‘E Y Y’ key sequences, followed by numeric input of length.

Each of the sides of the new plane is perfectly perpendicular to Edge A and exactly the same length as Edge B

Enter Vetex mode and snap Edge B’s vertices to the vertices of one of these sides

Enter edge mode and select extruded edge of plane

Enter vertex mode and delete verts

It looks a lot more complicated than it is. Total time it takes to step through this is about 15 seconds.

#5

Would this be an idea?

Snapping with Custom Transform Orientations in Blender from Bryson Jack

1 Like
#6

Thanks Minke,
This is exactly what I was looking for!