# Extrude by unit amount, not percentage

I've got a simple square plane (Blender 2.83) that is 66 x 66 meters and that I created by first adding a plane, then setting its X and Y dimensions in the n menu ("Item" tab in Object Mode) and pressing Ctrl+s in the end to "(Apply) Scale", so it afterwards also displays the right "edge length" in Edit Mode.

Now I want to extrude the corners to add a small border and make the plane 70 x 70 meters.

If I press e+s+2, the plane grows to twice its original size. To grow it to roughly 70m, I have to calculate the percentage (70 / (66/100) = about 106), then extrude with e+s+1.06, which is of course still a tiny bit off.

How do I extrude with the actual measurement I want to add, instead of the percentage, e.g.: make e+s+2 add a small border to turn a 10x10 plane into a 14x14 plane (hence, add 2 units on each side)? Is there another way to do this without using extrusion, while still easily and quickly creating new vertices on the outside?

Edit: You can find a screenshot what I want to do (but with units, not percentages) here. Please don't mind the glitchy look, I didn't clean up the double faces.

• i'm not really sure about your setup and your endgoal. how does the border you'd like to add look like? Could you show an image of what you have and what you want to achieve? Commented Oct 28, 2020 at 13:34
• Quick tip: turn on snapping (shift + tab) and use the mouse to scale to whole units. Commented Oct 28, 2020 at 13:36
• Basically think of a room: The overall length/width is 70 units (Blender is set to metric) and the wall is 2 units thick, which means that the inside of the room is 66x66 units, which is also my starting point. I use the extrude function to keep the 4 original corner vertices (which turn into the inside corners) and add 4 new ones (= outside corner vertices). This way I can easily extrude the the "border" (= the outside "ring") up (e + z) to create the actual walls.
– Neph
Commented Oct 28, 2020 at 13:44
• Don't use extrude + scale, but extrude along normals alt+E. Commented Oct 28, 2020 at 13:46
• I did, alt+e only extrudes along the z axis.
– Neph
Commented Oct 28, 2020 at 13:52

You can use inset for this.

Press i and type in the offset you need (in my case its 1 unit, so I end up with a inner square of 6x6 units.

Make sure Offset Even is checked in the bottom left corner.

• Inset is a bit buggy for me and only works half of the time but when it does, it does as shown in your images. Unfortunately you have to know at the very beginning how big you want your walls to be, so you can add that to the measurements of the floor, which I don't in my main project (at least not yet). Is there a way to make the inset work as an "outset"? I tried using a negative value but that didn't work.
– Neph
Commented Oct 28, 2020 at 14:57

Extrude along normals AltE and choose "along normal":

Once validated, you can use the operator panel to set the exact size you want. Also check "offset even".

Or, starting from a plane, choose inset I:

• That's what I did but it only extrudes up/down.
– Neph
Commented Oct 28, 2020 at 14:00
• The extrude along normals doesn't work like this on a plane. Commented Oct 28, 2020 at 14:01
• @bstnhnsl, sure but initially though he used a cube... as extruding make no sense is case of plane. Commented Oct 28, 2020 at 14:02
• You're in "Modeling" mode, right? When I switch to "vertex select" with "1" (in edit mode), select everything with "a", then press "i", I get the same dashed line as you are but there's neither a menu nor does it actually do anything. Plus, I want to place the new vertices on the outside, not the inside.
– Neph
Commented Oct 28, 2020 at 14:06
• I see, I have to type something to make the inset appear and the popup only shows up after I finish with enter. I tried, it won't let me use negative values though, which is no surprise for something called "INset".
– Neph
Commented Oct 28, 2020 at 14:13