I'm building a capacitor discharge spot welder for lithium ion batteries with 80 10,000uF capacitors arranged on perf boards, using bus bars to manage connections. I've run into trouble trying to tin the end of a thick stranded 1AWG wire to connect it to a mounting lug on a panel mount DINSE connector. My recent attempt led me to divide the wire into smaller groups, crimping lugs for 8AWG instead, since the soldering with a butane torch turned out pretty rough. I'm worried that these connections are not reliable, especially since they need to connect to the source legs of IRF3205 MOSFETs, which I plan to secure with epoxy after soldering. I'd really like to achieve clean, shiny, and secure solder joints this time. What's the best way to tin these larger diameter wire ends?
3 Answers
The key to a good solder joint is all about using the right flux! Go for a gel-type flux with a fine brush for precision. Just remember to clean off any residue afterward, as there are specific cleaners designed for flux removal.
Designing high-current stuff requires good connections. In the industry, it's common to use crimp lugs and bolts for hefty wires like 1AWG. Soldering a termination into a lug is standard practice, so don't hesitate to go that route if you're in doubt.
Try using fine grit sandpaper or emery cloth to prep those stranded wires, similar to what you'd do with copper pipes. After that, slap on the flux, heat it up, and then apply the solder. You'll want to see that nice, shiny finish!