dimensions and edge lengths don't match ?????

[solaris235]

I'm puzzled.
I'm modelling a building of size 34 X 24 units (actual - feet )
I've created my objects to the exact size that I want them.
As I keep working and adding other objects and details to the building I noticed that in edit mode with edge lengths on, the edge lengths of the over all dimensions don't add up to 24 or to 34 its slightly smaller. The dimensions in the properties tab are still set to 34 X 24 but the scale has changed to 1.047.
I would expect the scale to stay at 1. I have not done any scaling.
I don't understand how or why its changing.
If I change the scale to make the edge lengths add up the dimension numbers change. If I then change the dimension numbers back to what they should be then the scale number changes back and so do the edge lengths. I don't get it.
Any ideas ????


I can get the scale to stay at 1 and the dimensions and edge lengths to be close if I build an object by extruding edges and vertices but I loose accuracy. The edge lengths display an accuracy of 0.0 while the dimension and scale boxes display an accuracy of 0.000.

If I create a plane the default size is 2 X 2. If I set the dimensions directly in the dimension box in the properties tab to 34 X 24 then the size of the object changes. The dimensions are what I want, the scale changes from 1 to 17 , 12, 1 and the edge lengths in edit mode still display as 2 X 2
So the scale and edge lengths make up the dimension value.
I get how it works now, but its confusing when you want to be precise in your modelling.
Is there any way to get the edge lengths to display the actual number of blender units instead of the scaled units???

[hanpari]

Try to go to edit mode and press N.

Then check Mesh display-Numerics-Edge length"

I believe you will be probably suprised by displayed length.

Then go to Object mode and press ALT-S to clear scale and you find out that your object is back to 1 unit dimension.

To do what you probably want to do is:

1/ to set required dimensions to your object,
2/ then press Ctrl-ALT and choose scale.
3/ It will change your scale to 1 as you want.
4/ Now you can continue as you wish.

I hope it helped.

[solaris235]

Thanks for the reply.

Alt -s : sets the scalez back to 1 and changes the size of the object with it.

ctrl - alt - s : in version 2.64 is for saving the file - in version 2.37a it changes the scale to 1.

I can't find the 2.64 version of that command.

Any ideas where it might be?

[hanpari]

I am ashamed, the point 2 is my total mistake.

It is not CTRL-ALT but CTRL-A, in object mode you can find here:

Object-Apply-Scale

[solaris235]

Thanks very much that does exactly what I want.