At best, you'll get something like an almost 50% cut in the
voltage drop, all things assumed to be equal which is never the
case; a real world figure would be in the 40-45% range at a
nominal current, and possibly much less at higher currents.

So, uhh, why not do it right, use the correct derating factors
for that length run, and work accordingly. Most any wire has the
specs you need to be sure you won't hit the brownout margin for
your saw. Use 106Vac min and = 120Vac nominal for your calcs
and you'll be fine, and using resistive calcs (E=IR) will put you
in the ballpark for this; don't sweat the small stuff of
inductance and all that for this kind of calcs.
I don't subscribe to the "fix it later if it's a problem" when
it can be done right the first time and not have to be bothered
with again.

HTH,


"Toller" wrote in message
...
:I know it is unsafe to combine wires to avoid over loading a
circuit; like
: using two #14 to carry 18a. One could come loose and the other
is
: overloaded.
: But how about doing it to avoid voltage drop?
:
: I have no power at my dock, and carrying my generator down 130
stairs isn't
: any fun. I have done it once, and probably never will again.
: It is over 120ft, so a #12 extension cord would have excessive
voltage drop
: on a circular saw
:
: A guy is selling a 250 roll of 12/4 wire for $50. As far as I
can tell, it
: is something for audio hookups and has no ground. Could I
treat it as 12/3
: with an insulated ground, connect two of the wires together to
reduce
: voltage drop, and leave it as a permanent extension cord? I
figure that
: with two wires connected, the VD would be reduced to a
manageable level.
: (yes, I realize the return is only single, but it seems okay if
you average
: the two) There is no reason the wires should ever come undone,
but if they
: did, the worst that could happen is burning out my saw.
:
: Does this make sense?
: Is this 12/4 stuff safe for 120v?
:
: I did the same thing when I installed my transfer switch. All
I needed was
: 12/2, but I used 10/3 in case someone needed it in the future;
since the
: labor was the same either way. I connected two wires together
to reduce VD.
: A little overkill, but it was just sitting there anyhow.
:
: