In article om,
eljainc wrote:
Does anybody know what size power supply I might need for a typical
cordless drill motor?

For it to perform properly, an extremely high current one.

For example, I wish to power a 19.2VDC motor from black and decker/
Ryobi drill.

Don't think they've got the same maker. Ryobi is part of the Techtronics
group.

Could I get by with a 18VDC supply?

It's actually the peak current capability that determines the performance
rather than the voltage - unless that's vastly different.

What amperage would I be looking at?

If you want maximum torque I'd guess at around 20 amps. If all you want to
do is drill a few holes much less.


I think most of those battery packs are 2.4Amps.

That's the capacity in amp/hours.

If I put a 4 amp supply would that be sufficient or would that overpower
the motor?

A supply delivers the power the device demands up to the capacity of the
supply - not the other way round. But 4 amps won't be enough for tasks
which require full power.

I called DeWalt and the technical support person wouldn't tell me (I
think for liability reasons).

Because they probably won't know.

He said that people have tried to use a car battery to power a dewalt
drill and something exploded or went haywire on them.

Make that definitely don't know - about anything. ;-)

I'd ask why you're bothering, though, given the cost of a new mains drill.

--
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Dave Plowman London SW
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