Each and every bend in a piece of sheet metal has a certain minimum internal radius that needs to be taken into account when planning the design of a sheet metal form.
Bend radius for steel sheet.
Use this document to choose values that are both manufacturable and meet your needs.
It is possible to choose other bends if you require but additional lead time and tooling charges may apply.
You will need to know your material thickness mt the bend angle b the inside radius ir and the k factor k.
The material thickness will be measured in decimal form not by the gauge number.
Let s say i have a 2 mm thick sheet and i want to bend it.
Since commercial sheet metal bending can be done with less concern for stresses caused during forming operation the radius can be near zero for thin sheet metal.
If a piece of material is bent too tightly problems can occur.
It is most economical to use a single bend radius throughout the design but if necessary you can utilize multiple radii.
Bend radius throughout the sheet metal design is kept constant to take the advantage of using the same tool during manufacturing.
Minimum sheet metal flange bend length is required to avoid cracks in the bending area.
Minimum sheet metal bend length recommendations.
I can now see that the minimum flange length is 8 5 mm for such a bend so i have to keep it in mind when designing.
We go beyond the general rules of sheet metal bending as our customers want tight bend radii for sheet metal parts.
Bend radii minimum bend sizes.
The minimum bend radius data shown in these charts is measured to the inside of the bend.
The tables below show bend radii and minimum bend sizes for materials and tooling combinations stocked by protocase.
The bend radii listed are standard minimum if manufacturing for aircraft and aerospace applications.
The problem with bending too tightly.
In a previous bending basics article you mention a material s tensile reduction percentage used for calculating the minimum inside bend radius of various metals.
Larger bend radii require about the same force for bottoming as they do for air bending however smaller radii require greater force up to five times as much than air bending.
To keep it simple i also use a 2 mm inside radius.
The bend allowance formula takes into account the geometries of bending and the properties of your metal to determine the bend allowance.
Most frequently expensive sheet metal bending tools called brakes are used to bend sheet metal but you can also complete this task without one.
Divide 50 by the material s reduction percentage as specified by the material supplier subtract by 1 and then multiply by the plate thickness.
You described a rough rule to find a steel s minimum bend radius.
The most common problem with bending a piece of sheet metal too tightly is.