When sheet metal is bend, the inside bending surface is compressed. Whereas the outer surface is stretched. As a result, overall sheet length increases. This change in sheet length depends on the position of neutral axis or k-factor. Best way to calculate k factor in sheet metal is by reverse engineering. You can use this K-Factor calculator to calculate k factor using reverse engineering method. Cad tools use k-factor to calculate sheet-metal blank size. You can also use our flat pattern calculator for blank size calculation.

#### How to use This K-Factor Calculator in Sheet Metal

##### (Reverse Engineering Approach)

Step-1 : Cut a sample sheet and measure it’s total flat length and sheet thickness in mm. Strip width is not very critical.

Step-2 : Bend the sheet to 90 degrees and measure length A and B.

(Please note the bending of sample part is done in the same manner as we are planning for production. Because different machines and bending tools give different k factor values.)

Step-3 : Value of inside bend radius depends on bending tool and die. Generally it is considered equal to sheet thickness.

##### K Factor Calculator

• Inside compression in sheet metal cannot exceed the outside tension. Therefore k-factor value can not exceed “0.5” .
• Neutral axis cannot go beyond the middle of the sheet thickness.
• K factor Value is inversely proportional to sheet thickness. Increase in thickness, decreases k-factor value.
• K-factor value is inversely proportional to material hardness. Therefore with Increase in hardness, K factor value decreases .

#### Conclusion

To sum up, This calculator can be used to calculate sheet metal K-Factor using reverse engineering method. This k factor is used to calculate sheet metal flat length.

Got Questions?  We will be happy to help.

If you think we missed Something?  You can add to this article by sending a message in the comment box. We will do our best to add it in this post.