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Orrin
11-05-2007, 08:05 AM
I had a perfectly good 13.8 Volt Craftsman cordless drill, one good battery and two that would no longer take a charge. I objected to the obscene cost of a new battery (last time I checked it and sales tax would have been over $50.

So, I got a Harbor Freight 14.4 Volt battery for $10 and used the cells out of it to rebuild one for the Craftsman. It works like a charm!

If you value your time, I wouldn't recommend it, though. The Craftsman cells need to be arranged just so or they won't fit. I estimate it took me two hours to cut apart the H-F unit and re-solder everything back together.

I used 0.005" brass shim stock for straps to connect the cells. The added thickness on each end of the cell made the pack too thick to fit, so I used a burr to shave off a few high spots in the original case.

Would I do it, again? Probably so. It's satisfying to beat the system.

Regards,

Orrin

Bill Pace
11-05-2007, 08:53 AM
. It's satisfying to beat the system.

Regards,

Orrin
Heh! Yeah that is a sweet feeling.....

I did that a couple times with some batts already on hand, one a HF to HF, and another a Hitachi with HF's. One was a bit time consuming, the other I just removed one cell and it went right in.

With the cost of so many of the 12-14v cordless being so cheap it really doesnt make much sense I guess to do something like this, but........" It's satisfying to beat the system."

Pete H
11-05-2007, 10:05 AM
I'm in the same spot. I have 9.6V and 13.8V Sears drills, with dead batts. When the 9.6 died, I found that I could get the 13.8 with two batteries for about $9 more than the replacement battery alone... which, btw, would have been a special-order item.

Same thing happened when the 13.8 died, except that time, I went to Horror Fright and bought one of their $16.95 "over the left shoulder and no bad feelings" specials. That was last year, and it's still cranking. I really detest this "disposable tool" mindset, but money does indeed talk.

I did open up the battery case on the Sears 9.6, and found that I could get those cells from a local supplier - I think they're called "Sub-C" - but there was no savings: The replacement cells were about $7 each. I still intend to see if I can fit some AA NiCads in there - although as Orrin wrote, it'll be a real shoe-horn job. Something for a boring Winter evening.

Pete in NJ

hitnmiss
11-05-2007, 10:35 AM
rc car packs are a great source for sub C cells.

Usually 6 cells per pack. The one's arranged in two three cell sticks as opposed to side by side will have tabs welded on for easier soldering. Price anywhere from $15 per 6cell pack up to $80+ for matched racing packs.

In my experience better quality RC car packs cells typically last much longer than your average HF or equivalent cells.

snowman
11-05-2007, 11:23 AM
I need to do this on ALL of my dewalt 18 volt packs, but it seems that the cells cost dang near as much as a replacement pack....especially when you compare to the people on Ebay selling XRP packs at 95/pair.

gellfex
11-05-2007, 12:20 PM
I replaced packs for my DeWalt 14.4 with ebay NiMH packs at a pretty reasonable price, far less than the OEM NiCad. That drill has been beat to hell and still goes, dropped off ladders, immersed in water in a flooded basement. 9 years, not too bad.

wirewrkr
11-05-2007, 12:26 PM
Have any of you tried any of the battery specialty houses either local or on the net?
I have had good look with a place out of Florida, www.beiterbattery.com
they had some good deals on some odd motorcycle sealed batteries I was using, also the local Batteries Plus place seemed to have good deals on the individual cells that make up the battery packs.
Sears has sales on their batteries ocasionally, and imho, their price is a heluva lot lower than the price Ryobi wanted for the same friggin battery.
I believe Ryobi makes most of their cordless drills, or at least they used to.
Robert

Orrin
11-06-2007, 07:58 AM
Same thing happened when the 13.8 died, except that time, I went to Horror Fright and bought one of their $16.95 "over the left shoulder and no bad feelings" specials. That was last year, and it's still cranking. I really detest this "disposable tool" mindset, but money does indeed talk.

I did even better than that. When I bought my H-F 18.0 Volt cordless the store had run out of spare battery packs for it; however, the last time I paid them a visit they had identical 18.0 Volt drills on sale for $13!

Now, I have two packs plus a spare drill motor. That extra motor might come in handy because I smoked the old one a few times this autumn while driving 3" X #10 deck screws. For some reason, under certain conditions the motor would smoke before the slip clutch would torque out.

BTW, the 13.8V Craftsman performed almost as well as the 18.0V H-F unit.

Orrin

snowman
11-06-2007, 08:38 AM
how long do those batteries out of HF drills hold a charge?

Might not be bad for the dewalt, seeing as I never use it for the full length of a charge anyway. And the wife is sick of me using her drill.

A.K. Boomer
11-06-2007, 09:13 AM
My Norelco beard trimmer would have shot craps about 8 years ago (it was prob. 8 years old at the time) but its still going strong after tearing into it to replace one of the cells, had to make a special screw driver cuz Norelco doesnt wnt you fixin them...

snowman
11-06-2007, 09:20 AM
My Norelco beard trimmer would have shot craps about 8 years ago (it was prob. 8 years old at the time) but its still going strong after tearing into it to replace one of the cells, had to make a special screw driver cuz Norelco doesnt wnt you fixin them...

LOL

I generally just break it open and tape it back together.

-Snowman
"never been a watch maker"

A.K. Boomer
11-06-2007, 09:28 AM
I save the duct tape for things like my sandals and shop saftey glasses:p

Pete H
11-06-2007, 09:45 AM
Re charge retention on the HF cheapie drill... it's been very good, so far. The drill lives in the garage, it's been at least a month since I charged it, and I've used it half-a-dozen times in that month, for everything from spin-polishing a small part, to building an outboard-motor stand. I used it yesterday and it still has more torque than I can stall. But NiCads tend to die suddenly - one day they work, a week later they hold a charge for a couple of hours, then bupkis. I've never had any luck "re-forming" them by repeated deep-discharge, either.

BTW, I noticed one post about using NiMH batteries to rebuild a battery pack - were those used with a NiCad charger? And if so, did the charger and the batteries behave OK? Reason I ask, NiMH has a higher nominal voltage than NiCad, and the little AA charger on my desk has different settings for the different types.

Pete in NJ

Wirecutter
11-06-2007, 12:37 PM
I was trying to find the place where I got them, but no luck. I got a couple of boxes of 25 tabbed, SC size (sub C) nicad cells for about $25 each a while back. I've rebuilt all three battery packs for my Milwalkee 14.4V cordless with them.

Yeah, I think the battery retailers have gotten wise to the value of the sub-C cells, and many have begun to jack up the prices on them. $7 each is ridiculous. They should be closer to $2 each. If you look around, you can still find them.

-Mark

Orrin
11-07-2007, 08:08 AM
how long do those batteries out of HF drills hold a charge?

I can't answer that, for sure. Since I got my HF drill I've been using it rather regularly so I don't know if they are prone to self-discharge on the shelf.

Under heavy usage, the HF battery seems to do as much work as my Craftsman before needing recharging.

Orrin

5Bears
11-07-2007, 12:39 PM
For those of you who are just starting with a cordless "system" such as Ryobi, DeWalt, Milwaukee, etc, go for the Lithium batteries. They are more expensive intitially, but they have two huge things going for them. First, they have double the energy density of NiMH and NiCD batts, meaning they last longer and/or are significantly lighter. But to me, the big winner is the fact that they seem much, much more reliable. They don't have a "memory." You don't have to worry about being sure to drain the battery before recharging. And they simply seem to last longer.

I've bought many, many of those cheap 18V Ryobi tools, and they have all been winners with the exception of the dust vac, which is useless. But the batteries... ouch. I'd say of my original 6 or so, 3 died within 2 years and wouldn't take or hold a charge. I switched to Lithium and have been very happy so far.

The electric R/C flyer guys have been using lithiums for years, and they have pretty much rejected NiCD and NiMH in favor of the Lithiums. They do work well.