Curves are designed to make corners

[özgür]

Basic workflow
1) Make a bezier curve


2) Set the handles to vector


3) Model a mesh to extrude along the curve


4) Convert the extrusion to a curve


5) Set the bezier curves' bevel object to the extrusion


6) Check fill caps


7) Set the bezier shape to 2D in the object data tab


8) Extrude corners