# Bend straight object on corners 90 degrees

I've got the following object

and I would like to bend it at the corners, so something like this will be the outcome:

The measurements have to be the same. The small part in between for example has to stay at 12mm length/ width.

I tried using the spin tool but had no luck with it.

I would rather prefer to create the shape like this and bend it to my desired position and change the bend later on if I want to instead of modeling it from the beginning like my end goal.

• I'm not sure there's any easy solution, also if you rotate the selection 90° it will change the thickness so you'll need to correct that Jul 1 at 12:47
• Yeah, I did it with rotation right now and it's a mess.
– jona
Jul 1 at 12:48
• I would use bones for that... Jul 1 at 12:55
• yes you could use bones + Solidify modifier so that the thickness remains the same, it all depends on what's your final goal, it also takes time to set the bones, but afterwards you can bend the plane however you want Jul 1 at 13:01
• Yeah I think I go the bone way. Never done that before but will look into it. The solidify modifier is a good call. I can just use a 2D plane and make it thicker.
– jona
Jul 1 at 13:01

My version of it: at first I created a flat plane and made loop cuts in the middle, then split the plane into 3 separate faces by selecting the two edges in the center, right-clicking and choosing Edge Split. This will make the parenting to the armature easier.

Then I added an Armature > Single Bone at the bottom edge of the bottom face. I extruded it and adjusted the bones so that they fit to the faces.

After that I selected the plane object and the armature, hit Ctrl+P > Set Parent To > Armature Deform > With Empty Groups.

With the plane in Edit Mode I then selected the bottom face, selected the first vertex group for the bone at the bottom, made sure that Weight = 1 and clicked Assign. This I repeated for the second face and bone and of course for the third face and bone as well.

Now this will already work to bend the plane (as long as you restrict bending to the axis perpendicular to the face normal):

However, if I now add a Solidify Modifier, it will become obvious that I've split the faces (I've made it a bit thicker on purpose to show it better):

So in order to fix that, I put a Weld modifier between the Armature and the Solidify modifier. The position is important, because I want the mesh to be split for the bones, but it should be merged before I solidify it. Edit: I just tested it, after the faces are assigned to the bones it doesn't seem to matter if the Weld is before or after the Armature. I'll leave it here anyway in case of problems - the essential thing is, it has to be before the Solidify modifier.

• Really great, thanks! I almost did it on my own like this, but the modifier setup is the cherry that was missing. I chose this as correct answer because it's the most flexible and let's me change the angle. Because my 90° was only for example and the angle will change for different object!
– jona
Jul 2 at 10:13
• @jona You're welcome. By the way, I've used Offset = 0 in the Solidify modifier which places the thickness so that the original plane is in the middle of it. You might want to change that depending on the result you want to get. On very sharp angles I tried using a Bevel modifier before Solidify to round off the corner, but then you can get problems with Offset = 0, it's then better to have the thickness "outside" of the bending. Jul 2 at 13:35

Another way would be to individually separate the two flaps (p),

individually rotate them 90° (r + x + 90/-90), position them to where you want them to be (g + shift + x),

fill the open faces you would like to fill (f), select them (select the middle object last) and join them again (ctrl + j)

It may not be the simplest or quickest way, but it's how I usually do it if I don't want to hassle with bones.

Edit: You could use a solidify modifier for thickness instead of an extruded mesh and then rotate, the thickness won't go wrong.

This can be done using rotation...

Select your top edge of the small part. Then do Shift + S > Cursor To Selected. Now, go into face mode and change the pivot orientation to 3D Cursor:

Now, go into face mode and rotate the face 90 degrees by typing in 90 on your keyboard, on the respective Axis. In your case, press X. No repeat the same on the bottom edge of the small part and this time rotate the small part 90 degrees.

• Yeah, but this messes up the thickness... Jul 1 at 13:04
• @GordonBrinkmann Oh so it has a thickness in edit mode? Well then the best way would be using a 2d plane and add a solidify. Or use bones as you mentioned, (which I honestly am to lazy to do) Jul 1 at 13:06
• Though if we seperate the top faces by pressing Y, then rotate, and then press M > Merge By Distance to join again it would also work. Jul 1 at 13:07
• Yes, it has a thickness as you can see in the screenshot ;) All methods have their advantages and disadvantages, it mostly depends on how much time you want to spend on it and how editable you want it to be in the end. Jul 1 at 13:11
• @GordonBrinkmann yeah... In fact, I recently had to use this method to create a box opening animation. (not to mention I had to separate the faces to achieve my result in shape key 1 but it destroyed base, making me frustrated and remove the box opening animation completely) Jul 1 at 13:14

The best method I have found is with an addon called mesh align plus https://github.com/egtwobits/mesh_mesh_align_plus/releases/tag/v0.6.1

• Just links are mostly not considered good answers because you get no information what this addon does and if the link is broken one day or permanently offline, the answer becomes useless. Jul 1 at 17:51