NEIEP Mechanics Practice Exam

If the distance between the T-rail brackets is 8' 11", what is the back-to-back guide distance?

1. 8' 9"

2. 8' 10"

3. 8' 10 1/2"

4. 9' 0"

The correct answer is: 8' 10 1/2"

To determine the back-to-back guide distance from the distance between T-rail brackets, it is essential to understand that the back-to-back distance typically accounts for the width of the T-rails themselves. The distance given is 8' 11", which is the measurement from the outer edges of the brackets. To calculate the back-to-back distance, one must subtract the combined width of the T-rails from the total distance. T-rails commonly have a specific width, which, when added together, needs to be deducted from the total span between the brackets to achieve the back-to-back measurement. In many applications, the width of the rails can be around 2" each, leading to a total deduction of approximately 4". Therefore, when subtracting 4" from 8' 11", the calculation goes as follows: 1. Convert 8' 11" into total inches: 8 feet (96 inches) plus 11 inches equals 107 inches. 2. Subtract the total width of the T-rails: 107 inches - 4 inches equals 103 inches. 3. Convert back to feet and inches: 103 inches converts to 8 feet 7 inches. However, rail systems vary, and