Machining apparatus suitable to form electrode tabs (t1,t2,t3,...) comprising: - a feed path of material (M); - first machining means arranged along said path to perform a succession of working cycles alternating open positions, in which it leaves free the passage of the material (M), and closed positions, in which it performs at least one machining operation on the material (M); - second machining means arranged along said path to perform a succession of working cycles alternating open positions, in which it leaves free the passage of the material (M), and closed positions, in which it performs at least one machining operation on the material (M), said second machining means being arranged after said first machining means with reference to a feed direction (F) of the material (M); - first means for varying the period/frequency of the working cycles of said first machining means while the material (M) advances along said path; - second means for varying the period/frequency of the working cycles of said second machining means while the material (M) advances along said path, the period/frequency of the working cycles of said second machining means being different from the period/frequency of the working cycles of said first machining means ; - wherein said first means for varying comprises first guide means arranged along said path before said first machining means to receive the material (M) at a first speed (v1) and to deliver the material (M) at a second speed (v2), and second guide means arranged along said path after said first machining means and before said second machining means to receive the material (M) at said second speed (v2) and to deliver the material (M) at said first speed (v1).. - a feed path of material (M); - first machining means arranged along said path to perform a succession of working cycles alternating open positions, in which it leaves free the passage of the material (M), and closed positions, in which it performs at least one machining operation on the material (M); - second machining means arranged along said path to perform a succession of working cycles alternating open positions, in which it leaves free the passage of the material (M), and closed positions, in which it performs at least one machining operation on the material (M), said second machining means being arranged after said first machining means with reference to a feed direction (F) of the material (M); - first means for varying the period/frequency of the working cycles of said first machining means while the material (M) advances along said path; - second means for varying the period/frequency of the working cycles of said second machining means while the material (M) advances along said path, the period/frequency of the working cycles of said second machining means being different from the period/frequency of the working cycles of said first machining means ; - wherein said first means for varying comprises first guide means arranged along said path before said first machining means to receive the material (M) at a first speed (v1) and to deliver the material (M) at a second speed (v2), and second guide means arranged along said path after said first machining means and before said second machining means to receive the material (M) at said second speed (v2) and to deliver the material (M) at said first speed (v1).. <EOS>