Question

What is the parallelism tolerance of end faces of axes of rollers in sine bar according to British Standards?

(a) 0.013mm per 50mm

(b) 0.01mm per 25mm

(c) 0.013mm per 25mm

(d) 0.13mm per 25mm

I have been asked this question during an interview.

I'd like to ask this question from Sine Principle and Sine Bars in portion Angular Measurement and Circular Division of Engineering Metrology

Answer 1

The correct choice is (c) 0.013mm per 25mm

Easiest explanation: According to British standard, parallelism tolerance of end faces to the axis of the hinge roller is within 0.013 mm/ 25 mm and the accuracy of distance between rollers axes is 0.0025, 0.005 and 0.008 mm for 100 mm, 200 mm and 300 mm bars.