I finally got around to finishing the battery terminals. I started this process a long time ago. I replaced the negative side and realized I grabbed the wrong size battery cable lugs for the positive side. By the time I grabbed the correct size for the positive side, other projects had developed.
I snapped pictures as I always do and since there have been a lot of questions recently about how to do this, I figured I'd show you how I go about it:
First of all, I bought these from O'Reilly Auto Parts:
4 - 6 gauge with 3/8" Stud Hole - $3.29 per box of 2
Marine Battery Terminals - 5/16" Negative Stud and 3/8" Positive Stud - $5.49 for the set
For the negative side, I used solder lugs which can be a pain to find and wasn't much easier than the method I used for the positive side. The following method I used for installing the positive side works pretty well...
Alright, clearly, you need to chop off the old terminal. I cut it close to allow myself extra wire to work with:
Next, trim back the covering on the wires. I trimmed them back probably about 3/8" to 1/2":
Once trimmed, I applied flux to the bare copper:
I cleaned the inside of the lugs with a copper tube fitting brush (circular wire brush) and then fluxed the inside of the lugs:
Now would be a good time to slip some heat shrink over the wires...
Here's where it gets tricky without a spare set of hands (especially when trying to take a picture as well. You'll want to work quickly but if you end up moving too slow, you can fix any issues that arise.
Hold the copper lug with a pair of pliers. Heat the bottom of the 'bowl' with a torch and hold solder inside of the lug. I held it until the solder melted and almost filled the lug:
Now that the lug is full, you'll need to heat the wire. Do this gently. You don't want to be torching everything under the hood. You also don't want to melt the casing on the wire. The best method I've found (because you need to keep the lug hot as well) is to heat the wire while also holding the lug (with the pliers) at the edge of the flame. Once the wire is heated (and the solder in the lug is in liquid form), bend the wire down and cram it into the lug (wire down, 'bowl' of the lug up as to not spill out the solder). Hold it here for 30 seconds or so:
As you can see, I don't have heat shrink on my wires. I didn't have the correct size on hand. Fortunately, the lugs aren't too large so I can slip some over the top and heat shrink it down as soon as I pick some more up.
Slip the cover back over the wires and install:
And the finished product:
Installing lugs in this fashion ensures a solid connection. The heat shrink (yeah, yeah, still have to finish the positive side) helps seal the connection from the elements.
I've done my fair share of soldering and have dabbled a bit in copper plumbing work. For me, this took me between 15 - 30 minutes for one side including taking pictures. I could easily do all 4 lugs in under an hour (assuming all parts were pre-purchased). For someone new to soldering, it's quite simple. If the solder hardens up on you once it's in the lug, simply re-heat it. All in all, a 'newbie' should be able to do this in a couple hours.
Hope this helps!