Someone asked so I will explain. I posted some pics at www.album4392.fotopic.net that may help you understand.
Open the casing.
Look for the size and quantity of cells.
Purchase the cells at a large electrical components manufacturer (kind of place that sells capicitors,transistors etc).
I like to get the cells with no tabs as I use bits of tin as bridges, if you can only get the ones with tabs, they work but I find the tabs fussy. And a few of the tabs will have to be pulled off to make connections at the wider angles.
With the Mil 14.5 set up I take the old cells out of the casing and install the new cells in the container. Remeber this is a battery, each cell is 1.2V and you wire them “+” to “-” in series.
Now just copy the connection sequence between the cells from the old set. I start by soldering a dab of solder onto the top of each cell. Then I put the bridge on, push down with the iron, as soon as the dab flows I’m there.
Once the top is done (except the main connect) flip the conncected cells over in the casing as a unit and follow the connect sequence for the bottom (same as the turned over old cells.
At this point in a 14.5V battery you have 12 cells wired together in series, they fit in the case.
Now solder on the main connect, attach the top plate of the casing, charge it up and “Bobs your uncle”.
The whole thing takes me 30 min, I buy the cells for $3.00 each CDN ($2.00 US ?) it’s the kind of the thing I do during slow periods, It’s a bit cheaper than buying new, but mostly I do it cause it makes me feel good not to be giving Milwaukee, HD etc more $ than I need to.
Edited 2/20/2003 3:03:53 PM ET by PATRICKOFM
Replies
Now that sir, is just down rat in-jig-nee-us! Thanks for the tip!
Kevin Halliburton
"One machine can do the work of fifty ordinary men. No machine can do the work of one extraordinary man." -Elbert Hubbard-
Thanks for taking the time to explain this. I have a PC that is losing both batteries. I'd love to fix it for the reasons you mentioned. This might give me the motivation, if I find the components manuf. Do you get the batteries local or mail order?
http://www.digikey.com/
Has electronics stuff. From PC parts to whatever. Wonderful online store for the likes of Renaissance men & women
The easy move is to find the Values of the old part and search by that. There is about 7 to 8 bucks worth of minimum order charge and shipping cost involved in an order but it beats the stuffing out of making a trip to the store and talking to someone who doesn't want to see a 30 dollar order. I just used Digikey last week for some PC power supply capacitors. Slicker than snot on a door knob.
Jack of all trades and master of none - you got a problem with that?
Edited 2/20/2003 3:53:44 PM ET by Booch
What kind of soldering gun did you use?
I only have an old 15 watt one, which I doubt is up to the task.
Need one with "MORE POWER".
I don't have an attitude problem. You have a perception problem.
I feel strongly that you can't do much with less than a 35 watt iron. I have a couple of 25 watters that i couldn't get enough power out of to unsolder caps from a mother board. The 35 I had as well was just right. If you have to pick one for electronics 35 is it with a replaceable tip. Use rosin core solder no acid. It won't be big enough to lead glass but that isn't your intent anyway.
The reason for the lower watt irons is that too much heat will lift the solder pads on delecte electronics and too big a tip makes it hard to deal with integrated circuits and small points needing attention. How many hammers you own?
I was an IE in a Delco PCB assembly plant for 5 years. You wanna talk tools. I could spend 1500 on a collection of only soldering irons. There is some neat product out there. Glad to be out of the automotive.Jack of all trades and master of none - you got a problem with that?
Any good ideas how to get sealed plastic units open.
Jeff
Porter-Cable has 3 screws luckily.
I do it the easy way by having my customers pay for all my tools."One measurement is worth a thousand expert opinions"
PATRICKOFM, that's great! I have replaced just a bad cell in Makitas before (using other canibalized cells) but this sounds like the way to go. Some of the Makita cases will "unclip". Some of the old ones I have cut the end off with a hot knife blade and glued it back on with hot glue. It's pretty tight quarters in there.
I just called Batteries Plus in Peoria yesterday and it wasn't very cost effective to have them do it. Thanks for the parts address too. Fonzie
I have done much the same, replacing batteries in in the packs, for some time and had a good local source for the nicads. The problem is that the company went out of business and I haven't found another source. Where do you buy your batteries from?
An acquaintance who rebuilt his battery packs says he used the same cells that go in his RC cars. Those cars are the toy off-road cars controlled by a remote control. Cells are available from shops that sell to RC hobbiests, or on-line.
How about DeWalt batteries? I've heard some goo is poured around the cells making their replacement impossible.
jocobe
Edited 2/21/2003 7:08:29 AM ET by JOCOBE
JOCOBE, "impossible" just means "takes longer". You gotta look at it as a challenge. Come up with a "degooing" formula then get back to us. Fonzie
Didn't see anybody mention it, but soldering heat shortens the life of NiCd batteries, esp if you use a small iron and have to heat for a long time. That's why they come with the tabs. Best way is to spot weld on connections.
If any one has taken apart an original NiCd pack and found solder (vs spot weld)directly to the cell (vs a tab), I'd love to know who that mfg is.
I use a fine tip on a mapp gas torch to solder to the batteries and tin the copper strips I use for the interconnects before starting. I get a good solder flow in under a second and use a garden mister full of water to cool the whole thing before doing the next one. I used to wrap the battery with a wet cloth to keep it cool but I gave up on that when I realized the heat wasn't getting far enough down on the battery for the cloth to do any good.
I hold the battery in my hand, flux smeared on the surface to be soldered, and have the tinned copper strip with a bit of extra solder on the mounting surface in a vice. The torch in the other hand. Bringing all three together in one smooth motion. It goes quickly.
The manufacturers, at least all the connections I have seen, use ultrasonic welding. It too generates heat but it tends to be localized. Ultrasonic welders are a bit outside my price range. Counter intuitively the higher heat of the mapp gas flame limits heat damage by concentrating it and completing the joint before heat can be conducted to the cells. The final misting soaks up what excess heat remains.
I have a couple of dead 12V Makita packs. I cut one apart for grins (a Dremel makes quick work of cutting the case), and found 10 sub-C size Ni-Cads inside.
Well, I could buy 10 new cells, solder them together, and cobble the case back together. But I figured I'd end up with a cludge that's only ten bucks or so less than what you can get replacement packs for. I found a place on the net, http://www.batterybarn.com, that has has good prices on tool batteries. And for that amount of money, I have better things to do with my time.
I was getting good, better than most manufacturers use, batteries for about $2.25 ea. The ten sub-C cells run me $22.50. The battery pack goes for about $50. It took me, with a bit of practice about an hour to get it all together. $22,50 an hour is close to what I make on regular work and I like assembling the battery packs more than most work and even some recreations.
If I could get worn battery packs I would make up a dozen or more of these units with new batteries. I once had five good battery packs for my drill and it was grand. As soon as one slowed down it was replaced with a fresh one. It was like having a corded drill, unlimited full force run time, without the cord.
Good description of method to keep the heat out.
Have to admit I often resort to direct soldering also (esp on used batteries), but thought others may not have been aware of the damage they can do with excessive heat.
I'm with you on the comment " I like assembling the battery packs more than most work and even some recreations" ; also, you don't get taxed on that work <G>.
Have a number of Makita 12 V and 9.6 V drills I got really cheap (free to $5 ea) and have 'extended' the Makita 9000 battery packs by 2 cells so they work in either the 9.6 or 12 drills - 9.6 go like heck on high, never burnt one out yet.
Would like to try converting to Li-ion some day, but the raw cells are still too pricy for me compared to free used NiCd (about 70% have good life left), plus the charger circuitry would have to be redesigned.
How can you tell which have good life left. I have two dying PC packs. Could there be enough good cells between them to make one nice battery? How to tell? Got my trusty multi-meter. Is that any use?
Battery charger blinks it's red "bad battery" light with both packs, and PC said they're dead, too, but the one holds a charge for a fairly long time.
JUNKHOUND, are you saying you put extra cells in Makita 9.6 cases?
Also, this is a side issue, but would you mind commenting on this: I have 5 - Makita 9.6 drills almost 20 years old each (one right angle). My point on mentioning this is I have a good basis for comparison. All I have ever done is replace triggers and re-grease. One of them is "sick". It runs, but always as if the battery has 2 dead cells. What is your suspicion? I shined the flashlight in the little motor (can you believe the size of that thing?) and it appears the "brushes" are "globs" of carbon on flat springs. I'm wondering if all the carbon has worn off and I'm running on the spring.
Fonzie
Cloud: “ How can you tell which have good life left?â€
Lots of ways, here is one set of actions.
peel off he cardboard and look at the ends, set the ones with the white crust aside to start (this is KOH, and means the cell overheated at some point and vented, but not necessarily dead.
check voltage – probably good if over 1.25
for < 1.25 V, touch a 100 mA 20 V power supply leads to each cell’s terminals for 2 or 3 seconds and see if the voltage rises and stays up, may be a good cell
best way from there is to charge and then discharge thru a C/20 load and monitor the voltage (data logger or recording scope like the F123 is good for this ) and compare to specs, but usually just go with #5. Can also hook up a 1-1/2 volt bulb and see how long it stays lit.
quicker and easier way but not as accurate is to charge (you may have to charge individually if there was an open cell in the string) and then put your meter on the 10A range across the terminal very briefly, just enough to get a reading – you should get over 5A, closer to 10A or more short circuit current.
rebuild the ‘good’ batteries into a stack and tryout - keep it cool as 4lorns' post discussed if you have to solder directly to the case.
go back to the step #1 batteries, clean off the white crust with water and toothbrush and dry. Test as above – if ‘good’ fill annular ring with RTV and the little diamond in the terminal with RTV (the diamond is a little spike that is made to puncture a diaphram if the cell overheats and expands)
Fonzie …â€put extra cells in Makita 9.6 cases?â€
Not IN the cases, extended the cases – the drill then looks like a 9mm with a 30 rd clip.
"...what is your suspicion?"
The brushes should be recognizable as small rectangular blocks, if all you see is a blob, your ‘wondering’ is likely correct, esp. if it has seen long regualr use. I’ve got a 9.6 V 'freebie' that acts the same way, but have not torn it down, its in my ‘to do’ pile, but the keyless chuck plastic grip on it is so worn I’m sure it got LOTs of use.
Have also seen burnt contacts in the circuit breaker that's near the fwd/reverse switch; obviously, jumpering or replacing that fixes that problem.
I have two BK2300 12V Bosch drills and all 4 batteries that are all almost dead. My question is how do I open the plastic cases? There does not seem to be a glue line, so should I just cut the case? Where would be the best place for the cut? What would you use to cut it? Thanks for your help
Since you addressed this to me I'll answer; but, have never had a Bosch drill (nobody seems to give the old ones away!).
This is a little 'tougne in cheek' but remember when you were a kid trying to figure out the best way to get into a box turtle, or better yet, watching a dog try to get at one?
Best approach is to look it over real close, and if all else fails, cut at the bottom end about 1/16th from the outside, and be prepared to stop and restart - at least that will get you into the turtle, a Bosch anatomist I'm not <G>.
$2.25 is an awfully good price for sub-C NiCads. At that rice, if you like doing the work, it's worth it.
Fonzie.......you're a hoot, I've got some dead 14.4's and I just might experiment!
jocobe
Pat
How much to do two Dewalt 18 volters for me? Too much to do ..too little time?
Be charged
Namaste
Andy
"As long as you have certain desires about how it ought to be you can't see how it is."
http://CLIFFORDRENOVATIONS.COM
Thanks for the offer, but it's not something I can guarentee, and after the shipping and cross border taxes the price won't be so sweet either.