Cutting and stripping battery cables

We have started to recycle our old batteries, and would like to reuse the battery connectors, but the ends of the wires are bent and need to be cut and stripped. What tools would you suggest we use?

Use some heady duty wire cutters to cut the ends off, then a simple utility knife is usually good enough to remove the insulation so you can crimp on new connectors.

We normally cut them with large wire cutters or snips. We have a pair of wire strippers that work well enough but a box cutter also works, just cut around the insulation and pull it off.

We use these for all of our battery/main breaker wiring: Klein 11053. They have worked well for us, and aren’t too expensive.

Assuming we are talking about 6 gauge battery cables:

Cutting: A large set of diagonal cutters is best, like these:

Stripping: I’ve always used a utility knife for 8 gauge and larger.

I like these for cutting 6 AWG.

While we are on this subject, let’s not forget Al’s old tip, add a 10 star washer.

I personally like the type that Rich linked to. We found a smaller version that is perfect for #6 copper wire only. Do not allow the mechanical team to find them or they will be toast in a minute.
Use a box cutter/utility knife by simply rocking the blade until passes through the insulation. If you run the blade around the wire it will nick and cut and you will lose strands. When you have rocked the blade around the whole wire, then lay it flat on the wire and fillet the insulation until it is loose enough to pull off. If the wire is old and nasty looking, toss it. You will not likely get a good crimp and it won’t take solder as it should, if you solder your connections.

I’ve personally found that type to not cut as well as they are shears, not pinching cutters. Then again, it was steel wire that I was cutting.

Side note- I’ve always heard that if you nick off one or two strands (or a few for finer stranded wire, like 6 gauge battery cables) that it’s OK. I’m a bit of a perfectionist and cringe whenever I nick one when stripping (any gauge of wire) but perfect and satisfactory are two different things.

I’ve had mixed results with soldering battery cable lugs (or the leads to the breaker/PDP for that matter). The bolt-on kind (with screw clamps) I’ve had good luck soldering. However, soldering the crimp-on kind caused all sorts of trouble when I was on 1747 in 2010. We used a vice to do the crimping and torch soldered the crimp to the wire. The solder wasn’t conductive enough and we were tripping the main breaker due to heat, not current flow. Swapping to soldered clamp-type connectors fixed the issue.

Knipex or bust

They do make indestructible pliers… Although Klien tools makes good pliers too. My favorite Klien pliers is their 1005 cutting and crimping pliers, which are my favorite crimping tool for ring/fork/spade terminals and butt splices and double as a nice wire cutter (and do work OK as a 6 gauge wire cutter).

I linked harbor freight because the cutters I was talking about have held up fine for me if all you are cutting is copper. Knipex and Klien are better, but cost a lot more.

This - we use #95 05 165. Concave blade so you can cut wire and strip insulation in one step. Safer, faster, and more accurate than using a box cutter.

This is picture of the 6 cutters we use. Please note the warning on the handle, Do not use on steel.
We also use a vise to crimp our terminals. And we solder every one. It requires a large iron tip but we use a 35 watt iron. It is technique I have taught to our students. If you cut one strand from a 7 strand cable, you have increased the series resistance significantly. Cut off three strands from a 19 strand cable and you are doing the same. Cut off two of the 7 strands and you have reduced the wire to a 8.
As to heating the main breaker, that is the way it works. It is a bi-metal device. It is not the magnetic type used in house power panels. If it was tripping due to external heating, then poor connections can cause that localized heating.





At work and for FRC, I use a utility knife and cut about 2/3 to 3/4 of the way through the insulation, all the way around. This is to avoid cutting the copper strands (we mainly use the high-strand count stuff at work). I then bend and flex the cable at the cut, causing the remaining insulation to rip. The unwanted insulation can then be twisted and pulled off.

My “2 strands” rule was for wires with a larger number of strands. Like 10 or more. Also note that the copper strands do connect internally (inside the wire), so the justification was that it’s only missing for a short part, not the whole wire. Not nicking any strands is still a good thing though.

We used a butane torch to solder our vise-crimped cables… It seemed like everything was well connected. Obviously something was wrong, as like I was saying (and you are saying), the connection was too resistive and was getting hot, enough to thermally trip the breaker.

35W sounds a bit low… I’m not even sure my 60W Weller W60-P would have enough brunt to do a 6 gauge lug well. I’ve done them on 40W before but it was less than optimal. I’d recommend 100W, or a Soldering Gun (make sure the wires aren’t connected to any electronics!). I assume we are talking about the lugs connecting to the battery/breaker/(pre-2015) PDP, not Anderson connectors.

But if you guys (and gals) of all people make it work, then I really don’t know what to say. I guess “do what works for you, and to each their own?”

Though for the record, Al is magical enough he could probably correctly solder a battery cable using nothing more than a single match and the lead[1] from a pencil.

Team 2410 has a similar pair to the Harbor Freight 10" cable cutters, though ours might be a more generic brand. In the past to solder the connections, we used a butane torch.

[1] - I know they’re graphite.

Hi all,
Just a thought on the wattage of the iron.
We use an iron that is only 35-40 watts, but the tip is MASSIVE, like 1/2" in diameter, with a 5/16" chisel point.
This allows it to hold heat so it’s not so much the wattage of the iron heating your joint, but the heat transfer from the big tip to your connector.

Remember to clean the tip and tin it, and work fast so as not to melt all the insulation off the wire as you are soldering.

Works great!

Good luck, and have fun playing the game,

Mike

In most cases, it is not OK. The connection is already a poor conductor (relative to the rest of the wire), and adding resistance makes it worse.

It will be measurably warmer at the connection when a wire is nicked, and even mode so when strands are missing. (We’re talking 6 AWG battery cables here)

Thanks as I would’ve never thought of this. I might just suggest we organize our tools that all electrical tools remain separate from the mechanical team.

I was hoping someone out there would suggest that method philso. That’s the way I do it.

Dan