Same here although it wasn't a case of 'saving' a crank but rather one that came with a spindle that was too short on the left side. Tandem TA crank and the spindle that shipped with it may have been intended for a single. When tightened, the bolts on the inside of the cross-over chain ring rubbed against the bearing adjusting ring. Cut up a Coke can and put a shim around the square taper to hold the left arm out a bit farther. That was 42 years ago and I'm still using the Coke can shim whenever the bearings are regreased.