Take the 2-minute tour ×
Blender Stack Exchange is a question and answer site for people who use Blender to create 3D graphics, animations, or games. It's 100% free, no registration required.

I usually face this problem when I cut objects to make them printable in my 3D printer. As you may know, you need your object to have a nice base to be printed.

So I usually use bisect to cut an object to different pieces. As in this example:

Object bisected

and I need to rotate the top part to have a face as bottom:

Final Object

I'll share my workflow in an answer, but I'm asking for a simpler solution, if there were any.

share|improve this question

2 Answers 2

up vote 4 down vote accepted

So this is my workflow:

First select the face you want to be the ground of the object, and create a custom Transform Ortientation from the N panel:

Custom transformation

Then select the new orientation (and the object center as the face center)

Select custom orientation

Now add an emtpy, just in the object center, and align it to my custom orientation.

added emtpy align to transform orientation aligned empty

Now parent the object to the empty, clear the empty rotation, and clear the object's parent keeping transformation.

parenting unparenting

Finally rotate the piece 180º, and you have the face as the ground.

Final

share|improve this answer

You can use vertex snapping to achieve this effect.

Note before we begin: You can activate snapping by holding down Ctrl

  1. Enable vertex snapping
    enter image description here

  2. Select all the vertices along the edge of the cut face, then with the pivot point set to anything except active element, press Shift S > Cursor to selected

  3. Set the origin of the mesh to the 3D cursor(ShiftCtrlAltC>Origin to 3D cursor) If you don't want to move the origin, set the pivit point to 3D cursor.
  4. Add a plane in object mode. we will align the mesh to this plane. enter image description here
  5. Now with the mesh selected, hit R, (lock rotation to the axis of the cut mesh). With snapping turned on, move your cursor over one of the vertices on the plane.

Gif Demo:

enter image description here

Edit: This will work on multiple axis, first perform the snap on the X then the Y. I will note that it is incredibly difficult to get the snapping right. The best technique is to do the rotation in edit mode with snapping set to active.

share|improve this answer
    
The questioner wants to rotate the cut object so that the cut is flat along the bottom, not just rotate a plane to match the cut. –  David Jul 21 at 18:35
    
Exactly, you can rotate the mesh using snapping. I will add a .gif demonstrating this to the post in a second. –  GiantCowFilms Jul 21 at 19:14
    
Ok, now I get what you are doing. Sorry for editing your answer, when I did not understand what you where trying to do. As you probably guessed, I was rotating the plane, because the snapping is much more reliable. I have had trouble getting snapping to work when rotating many vertices, like the cylinder. –  David Jul 21 at 21:40
    
@David, no worries :). Getting snaps like that to work requires quite a bit of practice(I use snapping a lot). –  GiantCowFilms Jul 21 at 22:13
    
Nice one. But as you say, it seems it only works if you cut the object in one of the main views. –  DavidGasku Jul 21 at 22:22

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.