Not all wire is equal.
I loaned out my crimpers so a friend could re-do some wiring in his trailer. When he showed me his final work I suspect I broke his heart when I pointed out what type of wire he used vs. what type of wire he should have used. He used THHN (the sort you would get at the home improvement store) instead of automotive primary wire. The key difference here is in the stranding.
In this situation the wire is 6ga. THHN is stranded at that size, but nowhere near as finely stranded as primary wire. What this means is that THHN is flexible enough to be pulled through conduit, but not nearly as flexible as you want in a moving vehicle. The reason is work hardening. Lots of fine strands are able to move more readily than a few coarse strands, and able to move relative to each other. Think about wire rope (such as a winch cable). Now imagine replacing that with a single strand of steel. Bend the single strand back and forth a few dozen times and it will work harden and break, whereas that cable can flex back and forth hundreds of times (or more) without breaking.
Pay attention what type of wire you are looking at and learn its application.
Personally I like the cross-linked SXL, MXL and GXL wire types. For larger sizes welding cable is generally a good choice.
I loaned out my crimpers so a friend could re-do some wiring in his trailer. When he showed me his final work I suspect I broke his heart when I pointed out what type of wire he used vs. what type of wire he should have used. He used THHN (the sort you would get at the home improvement store) instead of automotive primary wire. The key difference here is in the stranding.
In this situation the wire is 6ga. THHN is stranded at that size, but nowhere near as finely stranded as primary wire. What this means is that THHN is flexible enough to be pulled through conduit, but not nearly as flexible as you want in a moving vehicle. The reason is work hardening. Lots of fine strands are able to move more readily than a few coarse strands, and able to move relative to each other. Think about wire rope (such as a winch cable). Now imagine replacing that with a single strand of steel. Bend the single strand back and forth a few dozen times and it will work harden and break, whereas that cable can flex back and forth hundreds of times (or more) without breaking.
Pay attention what type of wire you are looking at and learn its application.
Personally I like the cross-linked SXL, MXL and GXL wire types. For larger sizes welding cable is generally a good choice.
