Question

What is the permissible tolerance on flatness of side faces of sine bars of 100 mm as per IS 5359-1969?

(a) 0.001 mm

(b) 0.005 mm

(c) 0.01 mm

(d) 0.05 mm

The question was asked by my college director while I was bunking the class.

The question is from Sine Principle and Sine Bars topic in section Angular Measurement and Circular Division of Engineering Metrology

Answer 1

Correct option is (b) 0.005 mm

Easy explanation: As per IS 5359-1969, the flatness of side faces of sine bars of size 100 mm is 0.005 mm and the tolerances of squareness for side faces to upper face and parallelism of side faces to the roller axes are 0.003/25 mm and 0.01/25 mm respectively.