I give...what is the best way to solder large cables?

[brn agn]

One of my friends wrecked his 00 Dodge Ram truck last week. I spent two nights working on it so we could get it started and at least move it around (we are likely going to part it out). The impact sheared the positive battery cable in two near the battery. Since, we were trying to get the truck mobile without putting any money in to it, I soldered the cables back together with a large soldering iron. It works, but it is very ugly and I could not get enough heat generated to actually pull the solder through the wire. So, what is the trick for soldering large cables? Do I need a better soldering iron? Can someone list the correct steps involved in creating a reliable connection?

[dieselgeek]

Re: I give...what is the best way to solder large cables?

are you soldering two bare cables together? if so, this is a ghetto method but it works: fan out the strands a bit, dunk about 1" into a tub of flux, stick them "end to end" (butt join) then heat with a plumbing-size propane/mapp torch. Heat the wires before you stick solder into them. solder until it's dripping through the cable, then tape it. Good ghetto fix, I wouldn't do that on a daily driver though,

-scott

[TC]

Re: I give...what is the best way to solder large cables?

Go to Napa and get some battery cable unions it'll be a copper(or some metal) piece that kind of looks like a pipe, but on the inside there is a divider between the two sides. What you do is put the piece in a vice(or have someone hold it with vice grips) and heat it with a torch and then as you heat it melt a bunch of solder into it until it is full, then take the cable with the insulation stripped off and push it down into the solder let it cool and repeat on other side. You'll need to ask for "solder on battery cable ends" and then ask if they have a union.

[dieselgeek]

Re: I give...what is the best way to solder large cables?

TC explains the proper way to do it. I was thinking "absolute junkyard solution" hehe

[brn agn]

Re: I give...what is the best way to solder large cables?

Thanks for the responses. The cables are soldered "good enough" to move the truck around (I can only turn the steering wheel 1/2 revolution each way because the frame is pushed into the front tires), so I won't re-do my first crappy solder job. I will definitely try a torch the next time the situation arises. Heck, since the truck will likely be parted out, I may practice on it after we pull the engine/transmission. Anyone need some parts off a 00 Dodge Ram?

[cantvalve16]

Re: I give...what is the best way to solder large cables?

What color is the dash? My brother in law in GA. needs a new dash if that one is cherry.

I also used a small oxygen/mapp torch setup to make the cables for my car. It was the first tool I was actually excited about.

[dieselgeek]

Re: I give...what is the best way to solder large cables?

Yeah, what color is the interior? if dark grey, I need a driver's door interior panel...!

[squirrel]

Re: I give...what is the best way to solder large cables?

heat it with a torch and then as you heat it melt a bunch of solder into it until it is full, then take the cable with the insulation stripped off and push it down into the solder

I'd want to tin the wire first and make sure it's fully heated, just pusing the cold copper wire into hot solder will not make a good connection.

[Weldangrind]

Re: I give...what is the best way to solder large cables?

I used a small cigar-sized butane torch to solder battery clamps onto my friend's battery cables. The trick was to heat the wire and clamp considerably and then feed electronic solder in to the joint. Electronic solder is something like .030" and is easy to use.

[mrmustangman357]

Re: I give...what is the best way to solder large cables?

pics

[TC]

Re: I give...what is the best way to solder large cables?

heat it with a torch and then as you heat it melt a bunch of solder into it until it is full, then take the cable with the insulation stripped off and push it down into the solder

I'd want to tin the wire first and make sure it's fully heated, just pusing the cold copper wire into hot solder will not make a good connection.

Probably a good idea, but I've never had a problem not doing it.

[yellomalibu]

Re: I give...what is the best way to solder large cables?

heat it with a torch and then as you heat it melt a bunch of solder into it until it is full, then take the cable with the insulation stripped off and push it down into the solder

I'd want to tin the wire first and make sure it's fully heated, just pusing the cold copper wire into hot solder will not make a good connection.

I was going to ask about sticking a cold wire in hot solder. I've only had good luck soldering things that are both heated.

Probably a good idea, but I've never had a problem not doing it.

I'm not doubting you, just surprised that it works.

When I soldered the connector on the starter end of my battery cable, I dipped the wire in flux, crimped the end on (to hold it still), heated them both together with a torch, then filled it with solder. After it cools, apply heat shrink.
That method worked great... but next time I won't put as much solder in, because the cable was rigid about an inch and a half back from the connector. heh.

[squirrel]

Re: I give...what is the best way to solder large cables?

I did some #6 battery cables for the robots, clamped the terminal in the vise, put the wire in it, heated the terminal and the end of the wire with the torch, fed in about half a roll of .030 electronic solder. I suggest the bigger size of rosin core 60/40 solder for this stuff, they make it in 1/16" also.

[fabricatordave]

Re: I give...what is the best way to solder large cables?

when i was in high school teacher in electronics class used to scream at us good mechanical connection before soldering

if wire over heats it will just fall apart if solder is onlything holding it together

[squirrel]

Re: I give...what is the best way to solder large cables?

Yeah, it's a good idea to crimp it first. I'm still looking for an affordable big crimper.