What's that Lassie? You say that Stormin Mormon fell down the old
rec.crafts.metalworking mine and will die if we don't mount a rescue
by Sat, 10 Apr 2010 09:58:55 -0400:

Have you ever built a battery drill, using a dead
cordless drill, and external battery pack? For a
while, I was saving a 12 volt drill that was dead.

Yes I have. I had an older sears drill, and one of the
battery packs
died. After the autopsy, I soldered heavy zipcord to the
contacts.
A cigarette plug on the other end went into a AGM battery,
12v 6Ah.

CY: Now, that sounds good.
The whole rig is heavier, but it lightened up the drill a lot.


Draws a lot of power, about 20A.

CY: Did you measure it?

Yep. Current varies with load. 20A was the highest I got it with a
quick test. Might be more with a bigger load or different drill.
I think you could do some light drilling with a 10A limit.


I save it, becuase I figured I could put a length of
zipcord on it, and run it to a lighter plug. Power it
from the socket of a battery jumper pack.

Many battery jumper packs have a 10A circuit breaker.
CY: I can believe that.

You can open them up and add heaver wire and a bigger breaker, or make
up a lighter socket that you can attach to the jumper clamps.


Most Sub-C that I've found in drills are 1600 mA
hours, Compared to the cheap Rayovac NiMH AA
cells, which are about 2,000. could use a 12 volt
pack that runs AA cells (eight AA cells, Rat Shack
used to have these) and actually have more power
than the original pack. Plus, being able to test and
replace individual cells as they failed.

You might find that the AA cell packs won't handle that much
current.

CY: Well, that's very possible. I had not thought of that.

--

Dan H.
northshore MA.