Soldering in lugs?

Maybe an important point folks overlook is a tiny pencil torch for lugs up to 4 gauge and a mini torch for larger lugs.

Filling the lug does not work for me. I use 60/40 solder and paste flux. Flux the heck out of everything. Crimp lug to wire. Clamp terminal vertical (just an itty bitty piece of the terminal tip) in a vise or vise grips. Heat the terminal. This can take MINUTES be patient. When the visible dab of paste solder starts to bubble and melt get ready.

Feed a bit of solder between the lug and wire

If it makes a bubble, stop. Keep heating more. Watch the bubble.

When the bubble melts and flows the terminal IS NOT QUITE READY. Patience.

The terminal body will heat up before the copper wire does. So the solder bubble will melt vut if you start feeding solder now it will back up and overflow.

Feed -just enough solder to fill the terminal with a glob, keep heating and watch the glob. After a bit the wire gets hot enough to melt the solder. It instantly sucks the solder blob into the wire strands.

Start feeding solder. On a large terminal it will suck solder faster than you can feed it. Don't keep playing the flame on the joint, move it away now and then.

Finally! The joint fills up. The flux floating on top will overflow and then catch fire. Blow it out. You're finished...

No need to add the complexity of solder.
Crimp, Seal, Done.

There is a special 'art' when soldering connections that only a select few will master that over the years. I think will stick with my inexpensive $60 8-ton hand crimper. I know that always works for me...

After all is properly crimped in place then I too will add adhesive type heat shrink tubing to cover all of the open connections and seal-up from weather conditions.

Roy Ken

You can buy them with the solder already in them.