The measurement depends on the accuracy of the micrometer screw, which is cut and corrected with great care.
They are all provided with fine adjustment by micrometer screw.
The final adjustment is made by means of a micrometer screw attached to an arm which is clamped on the axle of the ring.
This was verified by moving by means of a micrometer screw the short arm of the lever through 0.005 mm.
The micrometer screw itself has a travel of one inch, like any standard micrometer.
Rotate the head of the micrometer screw until the movable line has transversed one division of the stage micrometer.
The top carriage can be moved by hand and accurately set by means of a micrometer screw.
The jaw end is counterbored out with a 45-degree counterbore to form a bearing for the forward end of the micrometer screw.
The adjustments of the objectives are accomplished by rack and pinion and by micrometer screw.
The screw and washer, marked H and I, go onto the end of the micrometer screw and take up the end play.