I did semi-truck split rims back in my tire busting days of the late 1970s. We would put the new tires on, install the split on the rim, put the wheel under a hoist, and lower the hoist until it contacted the rim. Then we would clear the floor of people and I would stand on one leg of the hoist as I filled the tube with air. We would let the wheel sit for a minute or two after the correct air pressure was acheived. The inflated tire sidewall would be compressed against the hoist leg and act as a safety dam in case the split ring didn't hold. We would inspect the split ring to make sure it was seated properly before raising the hoist. I only had one ring slip in all of the rims that I did. It did make me jump. Glad those things are gone.
