Cataclysm: Dark Days Ahead, or C:DDA, is an open source post-apocalyptic turn-based survival RPG that challenges players to not only survive, but battle a wide range of zombies and other terrifying creatures that threaten their lives. Newcomers are recommended to play the most recent stable release - 0.G - Gaiman
Fork of C:DDA with emphasis on combat, gameplay balance, and QoL
Multiplayer rewrite by /u/stolencatkarma
Cataclysm: DDA SSH server by /u/r7st
According to the HHG, welding rods and wires can be looted with high confidence from megastores, steel mills and some garages, with low confidence from light industry, parking lots, malls, pump stations, farm supply stores and other garages.
Light industry also sometimes has brazing rods, AFAIK, they can be used too.
Brazing rods are currently the easiest to make, just melt down every piece of copper you can find from homes (pots, washing machine internals, sinks, toilets, baths), alloy it with aluminum from rooftop gutters, and sprinkle in some detergent. EZ
With fences being transformed into mild steel, welding wires are tougher to make, but you can bleed acidic zombies and distill their blood into more usable acids for making these. It's also a good way to use lead-acid batteries you otherwise weren't going to use.