What is the annual table angle tolerance?

• A. 0.5°
• B. 1°
• C. 1.5°
• D. 2°

Answer: (B)

The concept being tested is how much the angle of a rotating table is allowed to drift over time, specifically the maximum angular deviation permitted after a year. This annual angle tolerance reflects how stable the table's alignment is under normal use, including effects like wear, temperature changes, and calibration drift. A value of about 1° is a practical balance: it’s tight enough to keep measurements reasonably accurate over a year but not so strict that maintaining it would be prohibitively costly or frequent. If you set a smaller tolerance, like 0.5°, calibration and fabrication requirements become more demanding; if you allow a larger tolerance, such as 1.5° or 2°, the angular accuracy could degrade enough to affect precise measurements. In many standard specifications and QA practices, 1° is the commonly accepted annual limit, which is why that option is correct.