SLU-70 Lugs

[The Lucas]

Originally Posted by sanddrag

I'm worried that in this case all you have done is created a "blob" (for lack of a better term) of solder. A good solder joint is a hot one, and hot solder joints happen quickly. You may have just filled in the gaps without providing any increase in mechanical or electrical integrity.

I have a question, assuming you only screw down the lug, do you get a better connection on more finely stranded wire? Like good welding cable as opposed to the junk battery cable they give us?

Originally Posted by eugenebrooks

If the solder flows through the wire and joint you have a good solder connection. Someone practiced at soldering will know what good solder flow looks like. I would not try to solder the SLU-70 lugs with a 25 watt iron, however.

That is a valid concern especially when working with a 25-watt iron. I can confirm it is a good hot solder joint. I had a student hold the iron on the bottom of the lug and I applied the solder directly to the top of the wire. As soon as the whole system heats up, the solder flows through the wire and down to the bottom of the lug. The result is a thoroughly tinned wired and bottom of the lug. We even avoided soldering the screw and clamp so we can still screw that down. It was also a good lesson on what it takes to make a good hot solder joint, and that student's small wire soldering skills improved.

Team 1495 works in a school metal shop and has few electrical tools. Soldering with a 25 watt iron is fairly dangerous, since you have a very hot wire and lug near your hands for about half an hour. However it is possible, so you could do it in a pinch. A micro torch is a better idea and that is what Team 365 is going to use on all the new SLU-70 lugs we had to use after we found out that rule at Pitt.