Classic overheated connection due to wire corrosion

[Lake-Effect]

Originally Posted by Spot

I would not blame the crimp itself. That is like blaming the hammer instead of the carpenter.

No, there are some inferior lugs out there, and I had this lesson driven home to me this year. I was using some cheaper yellow butt splices to join 2 #10 wires. (same size as OP) I was using good controlled-cycle crimpers. When I examined the crimp, the metal barrel was opening up at the seam, which wasn't welded. And I was able to pull the wire out (with considerable force)

I went out and bought some Ancor yellow butt-splices from the nearest marine store (at marine prices...) They had thicker metal AND there was no visible seam in the metal barrel. They took more hand pressure to crimp, but the resulting connection felt more solid, and the barrel wasn't opening up. And I couldn't pull it apart this time.

I'm sure there are other brands of crimp connections that are as good as Ancor. The ones in the OP's example and what i tried - with that visible, unwelded seam - are definitely inferior in my opinion, especially in that larger size that's carrying more current, and I won't use them again.

[donradcliffe]

My view is that even well crimped fittings should not be trusted with more than 50% of the rated amperage of the wire. If you want to carry 30 amps, use #6 wire,

The TSA stole my ratchet crimper from me when I tried to bring it aboard a flight this year. I have replaced it, but the new one is not nearly as good as the old. I also know that crimp fittings are not all the same quality, and I can't trust the crap Home Depot sells from China.

I'm not sure what the solution is. I recently tried soldering 5 ohm 25 watt resistors and #12 wire together to make a 2 amp 100 watt test load for my ebike battery. The solder joints melted apart after 10 minutes at 2 amps.

[Spot]

Originally Posted by Lake-Effect

No, there are some inferior lugs out there, and I had this lesson driven home to me this year. I was using some cheaper yellow butt splices to join 2 #10 wires. (same size as OP) I was using good controlled-cycle crimpers. When I examined the crimp, the metal barrel was opening up at the seam, which wasn't welded. And I was able to pull the wire out (with considerable force)

I went out and bought some Ancor yellow butt-splices from the nearest marine store (at marine prices...) They had thicker metal AND there was no visible seam in the metal barrel. They took more hand pressure to crimp, but the resulting connection felt more solid, and the barrel wasn't opening up. And I couldn't pull it apart this time.

I'm sure there are other brands of crimp connections that are as good as Ancor. The ones in the OP's example and what i tried - with that visible, unwelded seam - are definitely inferior in my opinion, especially in that larger size that's carrying more current, and I won't use them again.

L-E, good on you for checking your work, and upgrading the components to make things better. I will concede that there are good and bad crimps and that I should pay more attention to the barrels of the crimps I use.

[foufou]

While the crimp tool mentioned in the OP post is the most expensive I have ever heard of, the one I use - about $30- puts a dimple in the the barrel of the piece holding the wire. This effectively locks the wire in place and the little bit of barrel left un-crimped acts as a strain relief. Most of the original wire on my current boat is un tinned and has no issues.