One of the tools I acquried is a good old GB crimper.. normally used for smaller wire like 10 and up) I tried it on some 4GA lugs for an inverter.
Did a rather good job I thought. But then I have large hands (9 key spread on a piano) and fairly strong as well (old farm boy) And I cheated.
I'd not wish to try anything larger with those pliars though.
For 10 ga and smaller wires (10-12-14 ga) I have a die crimp tool, a ratcheting thing that produces a crimp that looks better than many factory crimps I've seen. It is specifically designed for anderson power poles but removing one piece lets me use it on any non-insulated lug of the proper size (Up to 10 ga).