With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Ken Russell directed the film Altered States.
text_B: The jig borer is a type of machine tool invented at the end of World War I to make possible the quick-yet-very-precise location of hole centers .. machine tool. machine tool. It was invented independently in Switzerland and the United States .. It can be viewed as a specialized species of milling machine that provides tool and die makers with a higher degree of positioning precision -LRB- repeatability -RRB- and accuracy than those general machines had provided .. milling machine. milling machine. Although capable of light milling , a jig borer is more suited to highly accurate drilling , boring , and reaming , where the quill or headstock does not see the significant side loading as it would with mill work .. The result is a machine designed more for location accuracy than heavy material removal .. A typical jig borer has a work table of around 400 x 200 mm , -LRB- 15.748 x 7.87402 inch -RRB- which can be moved using large handwheels -LRB- with micrometer-style readouts and verniers -RRB- on particularly carefully made shafts with a strong degree of gearing ; this allowed positions to be set on the two axes to an accuracy of 0.0001 inch -LRB- 2.5 micron -RRB- .. It was generally used to enlarge to a precise size smaller holes drilled with less accurate machinery in approximately the correct place -LRB- i.e. , with the small hole strictly within the area to be bored out for the large hole -RRB- .
not_related.