Latest Discussions : Tools & Workshop


12:34PM | 01/31/07
Member Since: 01/30/07
2 lifetime posts
I have several old power tool batteries that have died over the years... I really don't like buying them over and over.

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.
1827 replace a battery wi


03:27PM | 01/31/07
Member Since: 04/25/05
1915 lifetime posts
You can get batteries rebuilt for about 50-70% of new.

Do a google on it and you will find several sources.

There are several problems with what you want to do. The first one is weight and balance of the tool.

But how did you find out the current that the tools use when loaded? Batteries can produce a relatively high current surge.

Many of the smaller adapters only put out a small amount of current. The bigger ones can, but the design is such that they often need a minimum amount of load to work correctly.

And they often have too much ripple that can confuse variable speed controls.


03:43PM | 01/31/07
Member Since: 01/30/07
2 lifetime posts
That may be the problem; I don't know what the load draw is, only what the batteries are rated for. The only extra info I had was after-the-fact. The lumens of the flashlight only went up by 2% (possibly is how much more the old batteries could be charged?). But, we all know flashlight bulbs don't exactly draw much amperage ;-)

I wonder if I should go with a higher amp rated supply. Most things I've read say keep the volts as close as possible (exact is best), but that the amps don't matter.

I've even hear that for laptop batteries.

I wonder if that's true.....

In any event, would even an too low amp rating explain the was they run? The brief spurts of running, I mean? Or is that what you meant by 'ripple'?

BTW. The only 'local' places that will/can rebuilt are:

1) too damn high in price.

2) too far away (unrealistic to drive).

3) have multiple BBB marks against them.

Not all are every one, but you get the idea.

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