>> A two-part Q:

>> Due to some remodeling, I'm forced to splice/lengthen some old bx cable
>> that has #14 wire in it, and re-connect to the fuse box.
>> Should I splice the #14 with #14, or splice with #12?

>> The reason I would continue with #14 wire is just to remind me and future
>> people that Hey, this old wire is a little lighter than modern #12, and
>> to not take liberties with 20 or 30 amp fuses or breakers.  Other than
>> that, #12 would be fine with me.

> There's nothing "unmodern" about 14 for 15A circuits.

> I'd recommend sticking w/ same gauge as the original circuit for the
> reason mentioned.

> Remember to not bury connections in inaccessible places.

>> Next,  is there a rule of thumb for how many hot wires can share one
>> neutral of the same gauge?  If using different gauges, is there a "gauge
>> ratio", ie, some formula for cross sectional area between total hots and
>> total neutrals?

> Don't follow this question.  Each hot needs its own return neutral.
> If you're talking about 3-wire ("Edison") circuits, if properly wired the
> return is in effect a neutral w/ a balancing currents from the two sides
> if both are loaded equally; hence only the same size conductor is required
> for a single-sided load.

> If that isn't it, I have no clue what you're thinking.

> --