As technology is developing in all automotive companies, car body designers have also investigated new materials such as composite and aluminum alloys. Designing modern car structures has also created various challenges in the production process, including formability limitations. The main purpose of this research work was to develop a test setup for an open-hole uniaxial tensile test and investigate the effect of the cutting tool on the shearing edge quality of the series 6000 aluminum alloy and materials formability as a result. To approach this significant issue, detecting the onset of necking and forming limit curves FLC using 3D digital image correlations (DIC) capabilities were studied. Two methods based on strain rate for evaluating the instability through 3D DIC and Matlab were applied. Eighteen specimens in rolling, transverse, and diagonal directions were investigated. Although the results of the tensile test machine are close for all tests, due to 3D DIC limitations, detecting the onset of necking was hard to obtain.