Change the angle pivot of my object This is my first question! :D I'm ultra noob! but I'm getting better and better.

So: I want to change the angle of the pivot of this object.


Is like this now.


But when I want make a scale in X axis, this is happend.


So I belive that is one solution is change the axis like this for the scale thing... right?

How I can do that!

Thanks!
Let's you have this setup here, similar to yours:

 
Cylinder fits 2 cubes, but it's orientation is broken. And you want to fix it.
Create a Custom Transform Orientation. For this simple example: select the edge you want to align, press CtrlAltSpace or find it at bottom of the N-Panel.

You will have a new transform orientation that fits to geometry:


Now you can use this transform orientation for scale your object. But If you want to align object itself, move next.
In object Mode select cylinder, and press ShiftS -> Cursor to Selected
Create empty then press Object -> Transform -> Align to transform Orientation.
Parent cylinder to the empty  CtrlP.
Clear empty's orientation AltR. Cylinder will follow empty and will rotate with it like this:


Unparent cylinder AltP -> Clear and keep transform.
Apply rotation to cylinder  AltA -> Rotation
Rotate cylinder back ( Object -> Transform -> Align to transform Orientation. )