the tolerances to be adhere to are so minut that they can no longer be perceived with the naked eye Lonnegan now we're talking about an accuracy of three or four hundredths of a millimeter such dimensions pose quite a challenge in other words a component the size of a small bus must not deviate from the ideal by one hundredth of the width of a human hair to check this the Colossus is placed on Europe's biggest measuring table Engineers measure every opening every drilled hole indeed every square millimeter to ensure that no