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Convert a cordless drill to plug into a 12 volt battery pack when your battery packs die.
About twenty years ago, I sprang for a state of the art, best that money could buy, a Porter Cable 12 volt cordless drill. (the highest voltage then). It came with a charger, steel carrying case and two nicad battery packs. I got a lot of good use out of it over the years. About eight years ago, the battery packs started to die. I bought one new one for $50 or so, which has since died. At that point, I ended up with three dead batteries and a really nice drill that I couldn't use.
I intend to rebuild two of the batteries with new NiMH cells eventually, but for now, I decided that as long as it is a 12 volt drill, it can run from a 12 volt battery pack, of which I have several. This battery case was fairly easy to convert. Some of them may be harder or easier than mine.
You will have to open it up and engineer it to hold the contact plates firmly in place with the wires attached. If you want to do this with a drill that is less than 12 volts, you will have to determine a way to drop the voltage to a safe level. Putting a resistor in line is the simplest way. If your drill is a higher voltage, I don't know of any simple way to provide a higher voltage.
At every step of the wiring, it is a good idea to check the wiring with a continuity tester or ohmmeter to determine that the connections are complete and that there are no opens or shorts.
Before chopping, cutting, drilling, examine the components to determine the best path for the wires. It is a good idea to mark the ends of the base and top of the case to prevent confusion.
If you have problems with my instructions, drill a hole through your hand, set your hair on fire or burn down your house, all correspondence regarding these issues should be made to my attorney. You will be promptly awarded 16.4 million dollars after sending the appropriate handling fees to his PO Box in Nigeria.)
About twenty years ago, I sprang for a state of the art, best that money could buy, a Porter Cable 12 volt cordless drill. (the highest voltage then). It came with a charger, steel carrying case and two nicad battery packs. I got a lot of good use out of it over the years. About eight years ago, the battery packs started to die. I bought one new one for $50 or so, which has since died. At that point, I ended up with three dead batteries and a really nice drill that I couldn't use.
I intend to rebuild two of the batteries with new NiMH cells eventually, but for now, I decided that as long as it is a 12 volt drill, it can run from a 12 volt battery pack, of which I have several. This battery case was fairly easy to convert. Some of them may be harder or easier than mine.
You will have to open it up and engineer it to hold the contact plates firmly in place with the wires attached. If you want to do this with a drill that is less than 12 volts, you will have to determine a way to drop the voltage to a safe level. Putting a resistor in line is the simplest way. If your drill is a higher voltage, I don't know of any simple way to provide a higher voltage.
At every step of the wiring, it is a good idea to check the wiring with a continuity tester or ohmmeter to determine that the connections are complete and that there are no opens or shorts.
Before chopping, cutting, drilling, examine the components to determine the best path for the wires. It is a good idea to mark the ends of the base and top of the case to prevent confusion.
If you have problems with my instructions, drill a hole through your hand, set your hair on fire or burn down your house, all correspondence regarding these issues should be made to my attorney. You will be promptly awarded 16.4 million dollars after sending the appropriate handling fees to his PO Box in Nigeria.)
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Signing UpStep 1Parts and Tools
Parts List
Main Components:
- One old battery pack
- One cigarette lighter plug and cord, the heavier the better. Mine looks like about 14 gauge and holds a replaceable fuse in the plug. The cord
is about seven feet long. Try to find a cord that is long enough to comfortable reach the battery pack from where you will be working.
- Short length of rubber hose for strain relief that the cord will fit snugly through, about four inches.
- Fuse - fuse size is not critical. It is mainly to prevent a short circuit from causing a fire or meltdown. Probably a 5 amp would work. If it blows,
go larger.
- inline fuse holder (if your cord does not have one built in.)
- 2 or 3 tie wraps to secure the cord and strain relief
Tools:
- electrical tester for checking polarity, voltage, continuity.
- Soldering iron
- Screwdriver
- Diagonal cutters
- Drill
Main Components:
- One old battery pack
- One cigarette lighter plug and cord, the heavier the better. Mine looks like about 14 gauge and holds a replaceable fuse in the plug. The cord
is about seven feet long. Try to find a cord that is long enough to comfortable reach the battery pack from where you will be working.
- Short length of rubber hose for strain relief that the cord will fit snugly through, about four inches.
- Fuse - fuse size is not critical. It is mainly to prevent a short circuit from causing a fire or meltdown. Probably a 5 amp would work. If it blows,
go larger.
- inline fuse holder (if your cord does not have one built in.)
- 2 or 3 tie wraps to secure the cord and strain relief
Tools:
- electrical tester for checking polarity, voltage, continuity.
- Soldering iron
- Screwdriver
- Diagonal cutters
- Drill
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But I do have lots of car 12v Batteries whic i us as a power source for lights and stuff.
just need a old Battery to play with now lol as i dont wont to f up a good one.
I have the charger set on 12 volt. Amps can differ, I just get more rpms. I used this set-up to power a grain mill for 23 pounds of , malted barley for a beer that I'm brewing tomorrow. In the bag quit whining
Hard to tell, but sounds like you either have a short or incorrect wiring somewhere.
I would take it apart and check continuity at every point with a continuity tester. There should be continuity between each plug contact and the other end at the battery contacts, but no continuity between the two.
Compare your wiring with how the circuit is supposed to be. If your battery has three contact terminals, make sure you are using the right two. Temporarily touch 12 volts to the terminals inside the drill to make sure you're using the right one.
Can I run a cord from the charger directly to the drill? Does it have the oomph to power it well? Will it even work with a DeWalt charger (since it has the different modes)?
I've wondered (when the batteries were decent) if the batteries could be connected in series (based on the fact the inner cells are series) to the charger so more than one could be charging at the same time.
NOTE: APPARENTLY THE SWITCH HAS STOPPED WORKING. The motor still works when attached directly to power, but the trigger has stopped working.
If the switch is broken or the internal circuitry of the drill is otherwise damaged, it will not work. There is no way anyone can diagnose this problem without testing the circuit.
I suggest that you get a good battery pack and get it to work with that first. You can also use a tester to check for polarity and the proper contacts. Most battery packs have three contacts. I think the third one is for a thermal probe so the charger will know when to turn off or regulate the charging current.
If your polarity is reversed, it should still work but backwards and your direction switch will just be reversed.
As for using the charger itself to run the drill, I doubt that it has enough current. Chargers are designed to trickle charge with a low current, typically 1/10 of the normal run current. I see no advantage in doing that. It would require taking it apart and rewiring everything anyway. If you do want to use an AC adapter for your drill, it will require a DC output that supplies enough current to match what the battery has.
As for 'perfectly good', it was. Until I hooked it to my power source which was actually outputting closer to 14v (my fault, should have checked settings) it was still working just fine with batteries. I had just had that particular battery on the charger before starting this experiment.
The source I use is a little homemade power supply that handle a 200 amp draw. I assumed this would be okay because the power drawn from it should have been based on the need of the drill. I believe that whatever system the trigger uses to control speed is the problem. Going to see about a replacement trigger today.
Erm... sorry, but you are being condescending. I didn't know what VOM stood for (although given context and the letters I took a shot in the dark that proved to be right) but I've never heard those called VOMs, only multimeters.
Saying "if you don't know what this is for then you shouldn't be doing this" is OK if you are talking about a pair of scissors or a marker or something equally obvious, but using it on terminology that otherwise-well-informed people might not have heard just alienates people. Someone asked me what "flex" meant on one of my Instructables- I had to tell them it meant wire, and if you dont know what wire is for then stay the hell away from electrical projects, but it was just a difference in terminology.
Ranting aside, this looks like a good project. Now we just need an Instructable on how to deal with the people who say "hurf durf why did you attach a wire to a cordless drill now it's not cordless any more hurr".