m Ransley wrote:
The electronics amount to everything if they blow.

You got that right. And since engineers design to limits, it's
pretty UNlikely a 12V unit has 18V components. Nine to 12 maybe,
but not 18. These guys must be loved by the battery and
replacement parts shops, or they use their equipment a few
seconds at a time once or twice a year.
Then, even IF the components can live thru 18V vice 12, it's a
pretty sure thing the motor/stator windings weren't designed to
dissipate that much heat. Sooner or later one of these guys will
set the drill down after a prolonged session, the core temp will
work its way out thru the windings, and drip possibly flaming
plastic or winding cement onto the bench, and start a fire with
it, and then blame the manufacturer for their house burning down.
Way too many people think batteries are "safe" and that they
never heat up. The best part is the failure of a 12V while it's
on an 18V charger; it's usually a pretty site, at first. When a
battery core's max temp is exceeded, it almost always explodes or
vents with great gusto, especially the types used in power tools.
If you want to see a really pretty site, try a lead-acid on a
bigger charger; it's prettier yet, all that carbon to burn off.
Watch someone come back and say those batteries can't vent
'cause they have no vents g.

Don't drink & drill.

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