We will start by calculating the bend allowance.
Determine natural bend of sheet aluminum.
You will need to know your material thickness mt the bend angle b the inside radius ir and the k factor k.
The minimum bend radius data shown in these charts is measured to the inside of the bend.
Also know that for the best results and fewer cracks on the outside of the bend the bend line should go across or diagonal to the material grain when and where possible.
If your sheet metal is too thick you may need special machinery like a brake or a torch to bend your sheet into the desired shape.
The bend radii listed are standard minimum if manufacturing for aircraft and aerospace applications.
For most applications with stainless steel or aluminum you can get away with a zero radius bend on anything under 0 050 thick.
Bend allowance calculator the bend allowance and bend deduction are two measures that relate the bent length of a piece of sheet metal to the flat length.
90 degrees bend angle.
Choose a bend radius that matches your minimum bend.
Determine the thickness of your sheet.
With this free online tool we quickly get the sheet metal bend deduction and therefore the sheet metal blank initial flat length from the finished part measurements.
If you have any questions or want to discuss your design contact us.
The bend allowance describes the length of the neutral axis between the bend lines or in other words the arc length of the bend.
This measurement will be necessary for calculating your bend allowance.
After bending the sheet we need to do some measurements as shown in figure 2.
Cells on the right will output the desired values.
If you re bending 0 020 thick material use a 0 020 radius.
Figure 2 illustrates the sheet that is bent with the bend angle of 90 degrees.
The material thickness will be measured in decimal form not by the gauge number.
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.
You can use a tape measure or ruler to measure the thickness of your sheet metal.
Determine your minimum bend by measuring the distance from your closest feature i e.
In other words if you re bending 1 8 sheet use a tool with a 1 8 radius to form the inside of the bend.
From there we can calculate the k factor and the bend deduction.
Cut the section of metal out or otherwise prepare the metal to be bent by removing any burrs or sharp edges.
General advice on aluminum.
The bend allowance formula takes into account the geometries of bending and the properties of your metal to determine the bend allowance.
Determine the angle at which you want to brake the metal and mark it on the protractor.
When bending aluminum know that the smaller your inside bend radius the larger the chance that cracking will occur in the part.
