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Fixing Stuff
#11
Revisiting that electric screwdriver. This time, it's getting 18650ed. The problem is the NiCd cells keep self-discharging over times of disuse. As NiCds normally do. But it takes hours to charge them back up, and I want to be able to pick the darn thing up and just use it real quick.

So the obvious answer is Li-Ion! Just so happens that 3 NiCd cells in series is almost exactly the same Voltage range as a single Li-Ion. Or a single series of them. Anyway, I bought 6 brand new 20A cells a while back, and used 5 of them on a cordless drill I got at Good Will. But that's for an other post. The extra cell is for this guy.



The motor in this screwdriver has always been satisfactory for me, but the cells just don't last. A 20A 18650 should be more than adequate to provide whatever the motor wants. And I think it has more than twice the capacity of the original AA cells, which are long gone now.



I've also replaced the charging socket with one that is a match to my iMax charging cable. In the future, I could also make an adapter for a TP4056 board. Not sure what I want to do yet.

But a lot of internal structure had to be removed to make room for the new cell. It's a tight fit, but it works. Smile





The original charging brick, also long gone, was just a 120VAC to 4.5VAC transformer. A single diode rectified the current to the old cells. Shame on you Black & Decker for such a cheap system. I bet they could've fit a full wave rectifier and a capacitor in there for about the same price, and cut the charging time in half.

Anyway, no fancy electronics to adapt. And it works perfect. Even at only 3.2V. Gotta go put it on the charger though. Smile



Now I can get back to the other drill. The one from Good Will with the bad battery and no charger.

-Mike G
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