sorry I not native English, sorry for my English,
i look in this video on youtube :
in that machine seem to have some module or device to control how long a bar should be taken, some time about 20cm, other time about 10 cm,
what is that device called?
(look on the goods result, the length and width is different but the goods result is uniform)
note : i like to show you using images, but the forum only online picture available, i have upload it in attachment if you wanna see it