soldering battery cables

[Jan-78FJ40]

Title says it-what's the trick? I want to solder copper end lugs to 1 gauge battery cables. I am not getting these hot enough with my soldering gun. Maybe the gun is crap (20$ off ebay)? anyway, what are the tricks?

thank you,
J

 

[wesintl]

Jan,
I hold the copper lug with pliers. Heat the lug with a propane torch(benzomatic cheapies) and fill it with solder. I then insert the cable end.

 

[Jan-78FJ40]

Jan,
I hold the copper lug with pliers. Heat the lug with a propane torch(benzomatic cheapies) and fill it with solder. I then insert the cable end.

great one, thank you! I can probably manage that. no flux required either, right?

Jan

 

[spressomon]

great one, thank you! I can probably manage that. no flux required either, right?

Jan

Flux is a good thing...it'll give you better joint penetration/integrity...just use rosin core solder for electrical connects. And for the best joint be sure to polish, with sand paper, steel wool, etc., the lug and the cable.

 

[photogod]

I did mine like Wesintl but I kept the cable in the lug and heated it all together. I put an ample dose of flux in the lug after running some steel wool around in there and heated the cable along with the lug. The flux cleans the cable and the inside of the lug. Then touch the solder to the bare cable and let it wick in to the cable and lug. Watch how much solder you use as the solder will be wicked up into any part of the cable that is hot enough to liquify the solder and you could end up with an inch or two of very stiff cable. Also watch the fingers as the liquid hot F*#KIN flux leaks out of the bottom of the lug! Let cool a bit and dip in cool water to cool the joint and add your heat shrink. Done deal.

 

[rusty_tlc]

I use a bench vise with a couple of pieces of wood to hold the lug. Vise grips will also work, just pad the jaws with wood to keep them from acting as a heat sink.

I wouldn't quench the solder joint with water, that could harden the copper.

 

[Pin_Head]

Copper and copper alloys like brass do not harden when quenched. Nothing to worry about except using so much heat that you burn the insulation. Keep the heat on the tip of the lug and let it transfer to the joint.

 

[rusty_tlc]

Copper and copper alloys like brass do not harden when quenched. Nothing to worry about except using so much heat that you burn the insulation. Keep the heat on the tip of the lug and let it transfer to the joint.

I disagree.

Ask a gun maker about annealing brass parts. Copper also work/heat hardens, wire is annealed after drawing to return it to its more ductile state.

 

[nuclearlemon]

i use the solder with the flux core. same as wes except in the vise. been doing it that way for years with no issues.

 

[Jan-78FJ40]

thanks everyone!
J

 

[Pin_Head]

I disagree.

Ask a gun maker about annealing brass parts. Copper also work/heat hardens, wire is annealed after drawing to return it to its more ductile state.

We can disagree. I learned to turn copper plate to shape it, which work hardens it. We heated it and quenched it in water to anneal it so we could finish turning it some more. Heating it anneals it, but it doesn't harden like carbon steel if you cool it rapidly.

 

[Jan-78FJ40]

Jan,
I hold the copper lug with pliers. Heat the lug with a propane torch(benzomatic cheapies) and fill it with solder. I then insert the cable end.

worked like a charm, thank you!
J

 

[wesintl]

I forgot to say I wear gloves etc. I only gave the basics.. let you (or the others) fill or figure out the details

 

[rusty_tlc]

I use a bench vise with a couple of pieces of wood to hold the lug. Vise grips will also work, just pad the jaws with wood to keep them from acting as a heat sink.

I wouldn't quench the solder joint with water, that could harden the copper.

Copper and copper alloys like brass do not harden when quenched. Nothing to worry about except using so much heat that you burn the insulation. Keep the heat on the tip of the lug and let it transfer to the joint.

I disagree.

Ask a gun maker about annealing brass parts. Copper also work/heat hardens, wire is annealed after drawing to return it to its more ductile state.

We can disagree. I learned to turn copper plate to shape it, which work hardens it. We heated it and quenched it in water to anneal it so we could finish turning it some more. Heating it anneals it, but it doesn't harden like carbon steel if you cool it rapidly.

This has been bugging me. I respect your knowledge based on other post I have read, but your statement here contradicts my experience.

I did some research and it turns out we are both right, the alloys I am familiar with in the electronics industry are hardened by quenching and softened by anneling, other alloys are softened by quenching.

Copper alloys that are hardened through heat treatment are divided into two general types: those that are softened by high-temperature quenching and hardened by lower-temperature treatments, and those that are hardened by quenching from high temperatures through martensitic-type reactions.
Alloys that harden during low-to-intermediate temperature treatments following solution quenching include precipitation hardening, spinodal-hardening and order-hardening types. Quench-hardening alloys comprise aluminum bronzes, nickel-aluminum bronzes, and a few copper-zinc alloys. Quench-hardened alloys normally are tempered to improve toughness and ductility and reduce hardness in a manner similar to that for alloy steels.

 

[bsevans]

I use a crimper you hit with a hammer to marry the lug to the wire and then use mapp gas to solder with flux core solder. I then heat shrink with a weather proof shrink wrap. The orange alternator cable in the photo was done this way.