I got the bright idea (oh no), if I could find an ac adapter with the same volt and amp output, and I could fit it inside a battery case (take the batteries out of the housing), then I wouldn't need more than one or two batteries while I'm away from an outlet. (Most of what I do, I do close to an outlet. Having cordless tools are just very nice at times.)
Anyway, I found an adapter with the specs I needed.Got it home and checked it out on my meter (right on the money for volts; less than 1/2 amp higher than the batteries).
I emptied out a worthless battery, fit the adapter in, carved a hole for the cord and fit the wires inside to connect to the "battery" terminals.
PRESTO! Now it looks just like a regular battery, tests the same, it just has a cord hanging out.
When I put it in any of my tools, however, the tool runs in VERY short bursts and won't come up to speed.
What did I do wrong? If I use a variable speed tool and squeeze the trigger slowly, it sounds like it works great!
However, it is only acting! ;-)
Indeed, I can stop the drill with little effort with one hand and the sawzall will stop as soon as the blade touches wood.