My answer to What is the best way to design metal & steel doors and frames using CAD?
Answer by Scott Tarcy:
I utilize Solidworks so I will explain my answer using features in Solidworks.
First, you should understand how doors and frame are made in real life. For example, if you are talking about a car door, this is made by taking sheet steel and stamping it into shape. There will also be cuts made in it.
Frames are likely to be bent sheet steel. This is a different process. When making bends, one part of the sheet steel is held stationary and the other side is deformed by hand or my typically by robot.
I will show an example of each process in Solidworks,
This part is a protective housing of a plastic part (one half of the housing). This is an example of a stamped part. I made this feature by using the sheet metal commands in Solidworks, specifically the use of the FORM tool that is circled.
The next part is an example of a bent part. I also made this part using sheet metal commands. If you look at the folded part, each of those lines is a fold point (also called a bend point). The arrow points to one of these lines.
The main advantage of using sheet metal commands for a bent part like this is that you can “unfold” the part, as shown on the right side of this picture. A flat part is needed for a manufacturer to know the cutting lines to make the shape from sheet steel.
If you had modeled this using traditional commands (boss extrude, cut extrude, etc.) and not the sheet metal commands, then you would not have the ability to unfold the part.