Above is a clearance chart from 1979 of Vulcan’s onshore air/steam hammers. The clearance chart is helpful in that it can show whether your Vulcan hammer can fit into a given set of leaders.
One thing to keep in mind is that, if your leaders have a low distance from the front to the back rail, small clearance may not be your only problem. The distance from the front to the back rails on U-type leaders is a major part of their strength; the larger that distance, the higher the section modulus of the leaders for given front and back rail configuration.
vulcanhammer.info 
One thought on “Onshore Hammer Clearance Dimensions”