In principle does not seem that this operation is complicated and difficult.
How to bend 4mm steel sheet.
The bending of sheet metal with a punch and an array mounted at a folder is quite natural and normal.
If you need to reheat the metal and redo the bend.
Choose a bend radius that matches your minimum bend.
I doubt that you will get it hot enough to bend easily with a propane torch as you will need all the area you are bending at least cherry red and preferably hotter.
Understanding the bend allowance and consequently the bend deduction of a part is a crucial first step to understanding how sheet metal parts are fabricated.
Bending is one of the most common sheet metal fabrication operations.
How to bend sheet metal without a brake in 4 different methods with minimal or homemade tools.
However there is a limit to the feasible width height ratio of the u shape.
Also known as press braking flanging die bending folding and edging this method is used to deform a material to an angular shape.
How to bend sheet metal without a brake.
Grab the top of the metal with the pliers as the section you heated cools off and pull towards you gently at first.
When the sheet metal is put through the process of bending the metal around the bend is deformed and stretched.
Now that you know your bend allowance take your protractor and draw a clear line with your marker across the point at which you will bend your sheet metal.
Find somewhere with a hydraulic press and formers to do it for you and slip them a tenner.
Mark your bend lines.
Bend radii minimum bend sizes.
The metal should bend but only bend it as far as it goes without forcing it.
Determine your minimum bend by measuring the distance from your closest feature i e.
This is done through the application of force on a workpiece.
The force must exceed the material s yield strength to achieve a plastic deformation.
A cutout or the edge of your flange to your bend.
4mm thick is not sheet it is plate.
As this happens you gain a small amount of total length in your part.
May you live in interesting times.