The bend deduction is the amount the sheet metal will stretch when bent as measured from the outside edges of the bend.
Sheet metal bending inner radius.
You will need to know your material thickness mt the bend angle b the inside radius ir and the k factor k.
Bend radii minimum bend sizes.
When designing sheet metal parts and enclosures it is helpful to use these values as the basis for your design.
Material thickness or 0 1575 in.
As another example say you re working with 0 125 in thick material.
Wipe bending or edge bending is another way to bend sheet metal edges.
In this case the minimum producible inside bend radius is 63 percent of that 0 250 in.
Because 0 125 multiplied by 63 percent gives you 0 078.
The minimum bend radius for mild steel sheet metal should be equal to the thickness.
The u punch forms a u shape with a single punch.
The bend radius refers to the inside radius.
Let s start with 90 degrees bend which is the most simple scenario.
The slack between the wipe die and the punch plays an important role in getting a good result.
Therefore the bending inner radius of our sheet metal parts is basically 0 2.
The more ductile the sheet metal the smaller the inner bend radius is possible.
It is important to make sure that the sheet is properly pushed onto the wipe die.
As a result the wipe die also determines the bend s inner radius.
Bend radii and minimum bends are limited to certain values or ranges which are determined by the equipment and tooling combinations available to the manufacturer.
It is most economical to use a single bend radius throughout the design but if necessary you can utilize multiple radii.
The material thickness will be measured in decimal form not by the gauge number.
For this a bend turns sharp at a radius of 0 078 in.
For ordinary low carbon steel plates rust proof aluminum plates brass plates copper plates etc the inner radius 0 2 is no problem.
Flat sheet 90 degrees bend angle.
The bend allowance formula takes into account the geometries of bending and the properties of your metal to determine the bend allowance.
Say you re bending soft 13 ksi aluminum with a 0 984 in.
Just as a starting point you calculate the inside bend radius at 16 percent of the die opening to be 0 157 in though this is for 60 ksi material so you ll need to adapt to the material type.
The bending tool has a radius of 30 mm which means that our inside bend radius r is 30 mm.
The sheet metal design rule of thumb in this case is.