Soldering 4 ga Connections

Since I have enough marginal vehicles to always be jump starting something I decided to install an Anderson quick connect plug in the grille of the truck to mate with corresponding jumper cables. They make kits to do this, but they are quite spendy for what they are. Already having a good set of 4ga jumper cables I set out to build my own. I purchased three Anderson plugs, some welding wire for the truck side connections and corresponding terminals / lugs.

My issue comes in trying to solder these terminals. I can solder small gauge stuff, but have been put to shame by these. Any tips for soldering bigger stuff? I tinned the bare copper and heated the terminal with a propane torch, but in a few tries the most solder I could get to flow was about 1". At that point I was putting too much heat into the wire and melting the insulation farther up.

Should I continue this endeavor or try to source the hammer crimping tool? Terminals are rated for both solder / crimp. I read the thread on merits of each method and hope not to start that debate again. Any tips?

I just did an entire car's positive and ground setup like this. The hammer crimp tool was helpful, but I soldered it all as well.

Use heat shrink, cut back insulation a good inch past the terminal. Torch the terminal stick the solder in there, fill the sucker up.

I found I had to use smaller gauge solder than I thought I would.

berkeley the soldering on big cables. These set ups have never let me down and the two i did 15+ years ago show no signs of needing to be cut back like so solder ones done at same time due to acid in the flux getting traped.

http://pitstopusa.com/i-5059077-moroso-battery-terminal-end-kit-battery-cable-remote-fitting-end-kit-3-8-opening.html?gclid=CP6kkq723bUCFUVN4Aod7XQACA

They come in difrent styles too side battery, top post ect. Shop around i just googled so price might not be best.

Crimped connections are correct in this application.

On big-but-not-this-big I sometimes solder, but use a BIG iron, and rosin core solder.

Acid flux doesn't belong anywhere there's electricity other than a grounding path involving a copper water feed line.

we used acid flux on some of our resolver headers(used for tinning the areas to be soldered only) ... but there was a very strict and intensive cleaning/neutralizing process with (VERY) intensive inspection afterwards with a lot of rejection and re-cleaning/neutralizing ... acid flux is awesome for cleaning the, to be soldered, area .... that said if you don't have the neutralizing process in place then the long term effects can be devastatingly destructive

Basic rule, NEVER use acid flux for electrical systems.
Rosin based flux does a great job.

The problem with large joints is getting enough heat into them quickly, without melting or burning all the non-metal pieces that may be attached or nearby.

You never melt the solder directly, instead you heat the metal in the joint until it's hot enough to melt the solder, and apply it then. The solder will melt and 'wick in'.

Another approach uses solder paste, which is powdered solder mixed with liquid flux.
You can apply it cold, taking care to fill all the spaces inside, then quickly heat the outside of the joint with a stout torch to get everything melted.

I made some 25 ft jumpers out of 'surplus' welding cable, and soldered the clamps using that method.

Carter

You should be crimping, not soldering. Every terminal or lug you got in that size should have been designed for a mechanical (crimp) connection.

Bryce

I haven't yet attempted this technique but it looks promising.

http://blog.iimuchfabrication.com/?p=360#more-360

Obviously rosin solder, then propane or mapp gas torch, terminal clamped in a vice with the wire receiving part up like a little cup.

Heat the terminal up until you can melt solder inside it and fill it part-way full of molten solder. While applying heat, dip the end of the wire into the molten solder until the wire gets hot enough the solder starts to wick up the wire, at which point you bottom out the wire and remove the heat. Hold it all until the solder cools, or if it means something to you quickly clamp the vice to crimp the lug while everything is hot.

One of my previous bosses did this for everything, and had a high level of success as long as after it was cooled he cleaned off the resin and covered the works with heat shrink.

Later the same guy bought one of these and he never bothered with the heat again. He had about the same success rate without the hassle.

I have one like this, and with my trusty welder and a 4" grinder I have modified several $19 HF bolt cutters to look the same for friends.

i have done it with propane torch and with butane mini-torch, both with good results. remember to slip the heat-shrink tubing onto the wire before soldering, LOL.

Given the recommendations above and my poor luck with soldering I will plan on crimping. Either Harbor Freight or borrowing the correct crimper from work should set me up. I had never seen the compression style clamps that 44Dwarf recommended. Will try to remember those for any future projects where heat may be a concern.

erohslc wrote: Basic rule, *NEVER* use acid flux for electrical systems. Rosin based flux does a great job. The problem with large joints is getting enough heat into them quickly, without melting or burning all the non-metal pieces that may be attached or nearby. You never melt the solder directly, instead you heat the metal in the joint until it's hot enough to melt the solder, and apply it then. The solder will melt and 'wick in'. Another approach uses solder paste, which is powdered solder mixed with liquid flux. You can apply it cold, taking care to fill all the spaces inside, then quickly heat the outside of the joint with a stout torch to get everything melted. I made some 25 ft jumpers out of 'surplus' welding cable, and soldered the clamps using that method. Carter

I'll repeat what I said above.... the probation on using acid flux on electronic parts isn't 100% true ... the parts we made were electronic parts going into aircraft ... (both military and civilian ... including the space shuttle , and the space station )

some metals don't take solder tinning very well ( or at all ) and it does take acid flux to "etch" the metal to the point where it'll take the solder ... and if possible you should always tin the parts to be soldered ( NASA level solder certified ) .. but you DO have to clean/neutralize like hell ....( like I mentioned above also )

Sure, acid flux can be done in a controlled industrial setting.

But we ARE talking Grassroots here, right?
And we ARE talking copper cable, not exotic metals, right?
And it IS multistranded cable, the kind where the acid flux can wick into the middle of the bundle, past the insulation sheath, making it VERY difficult to clean and neutralize, right?

If you are sweating copper pipe and fittings, acid flux works great.

If you are building heavy electrical distrubution systems with fabricated busbars, blocks, and terminals, acid flux works great.

If you are building microwave diplexers and other such assemblies, acid flux works great (although we used rosin flux successfully on ours),

This, since above are (relatively) easy to inspect, clean, and neutralize.

For just about anything else electrical, especially if you are in the field or DIY,
I'll repeat what I said above ...avoid acid flux.