Solder, Crimp or Screw terminals?

[amalventano1 at tds.net (Allyn)]

> I have had good luck so far with solder terminals, puddling them with solder and dunking hot 
> > wire into them.

Perhaps, but that is a sure way to get a cold solder joint.  There would have been no time for the solder to properly bond to the
colder wire for a proper connection / bond to occur.  If you pre-tin the wires it will make things a little better, but you'd have
to get both hot (molten) simultaneously and get them where you want them before the solder temp dips through the plastic region.

> I was looking at using the P3 stuff for 
> some ground 
> > wiring on the new car, but I don't have faith in the screw 
> terminals.
> > 
> > What say you?
> > 
> > Brian

For large connections like this, which carry a bunch of current, I'd go with those screw-type connections over solder.  Use some
dielectric grease and you'd be good.  The problem with solder in a high vibration connection is that it will make the braid rigid,
and the point where it stopped wicking itself down the wire will become a stress point unless some form of stress relief is added.

> - Dunk wire into NON-acid based rosin, and pre-tin the end of 
> the wire/cable

Acid-core rosin is designed such that the rosin cleans the surface just prior to flashing away as vapor.  If you get the solder hot
enough to properly flow, chances are it was also hot enough to vaporize all remaining rosin.

> - After things have cooled and there is a confirmation of a 
> good connection, coat the new end with something to keep 
> moisture and O2 out.

That is the other reason I try to avoid soldering wires under the hood.  Dissimilar metals (copper/lead+tin) and moisture don't mix.
Crimp/screw connections have the luxury of using copper / gold / otherwise more closely matching the electrode potentials of the
wire.

If you must solder, get the junction hot *first*, then add solder - it flows towards heat.

On the subs, we crimp/screw anything larger than about 12 gauge or so, and especially if it is not within its own enclosure and
secured to the interior downstream of the joint (stress relief).  Basically, if it's not going to/from/within a circuit card or
motherboard, it's crimped or screwed.

HTH

Allyn Malventano, ETC(SS), USN
(Qualified to solder/repair the stuff that keeps reactors safe in a depth-charge / salt water environment, which means I usually
have to fix/solder everything else on the boat)