I will be mounting a sprocket gear on the 2 inch input shaft to my custom piece of industrial machinery I am preparing. The sprocket gears are available in 1 15/16 and 2 inch bore diameter. Would there be an advantage to having the end section of my shaft turned down to 1 15/16 in ? I feel like if the shaft was a bit smaller in that section, it would help keep the sprocket in place, and act as sort of a built in snap ring to hold the lateral position of the gear.
The word you're looking for is "shoulder". It might help but it's kind of pointless during operation if you are using a setscrew. Might help with assembly I guess since there is less thinking involved If it were square or D-shaft it and no setscrew then it would help since you would only need one snap ring or shaft collar.