Can I run drill off of car battery

[anoldfart2]

I got one of those Skil 12 volt battery drills. The battery charger died. Skil told me the battery probably shorted. Well, by the time I finish getting a new charger and battery, I may as well get a new drill. I am not fond of Skil anyhow. However, rather than toss the old drill, I am wondering if anyone has ever run one of these off a car battery? I can easily rig a lighter plug and hook some wires to the drill. It needs 12 volts and thats what the car battery is. At least this way I can still use it around the car, and I also have a

12v gel cell so I can use it portable.

[Patrick Cleburne]

The voltage is right but the amperage may be way too high and fry the drill-- but then if it did, no real loss.

[CJT]

but the amperage may be way too high and fry the

Huh?? How so?

[Steve Kraus]

Yes but whatever you do make sure it's fused. A lighter outlet on your car is of course at the car's fuse panel and you can also use a type of lighter plug that contains a fuse but if you're doing anything involving direct connection to a car or other similarly large battery use some kind of in- line fuse holder. A car battery can put out a huge amount of current in a short, enough to melt small gauge wire and there's always the possibility of a hydrogen explosion at the battery.

[D Duddles]

The lighter outlet will probably be fused at somewhere between 10 and 20 amps in the car's fuse block, depending on if it's actually a lighter outlet or an Aux. Power Outlet (same size, but the Aux. Power Outlets sometimes have higher fuse ratings and heavier gage wiring to power external devices, and also may not have the clips at the bottom to retain the lighter element when it's pushed in). In any case, make sure you either use wires that are large enough to support the maximum fuse rating of the outlet, or put in a smaller fuse to prevent turning your "extension" wires into a heater (especially if there is an internal short in the drill that destroyed the original battery). There's not much danger of a hydrogen explosion of the car battery, since the car's fuse will blow before you can draw that much current from it.

[Edwin Pawlowski]

Sure, many people have done it. Biggest problem is getting the car close enough to the work, especially if you are putting up curtain rods in the upstairs bedroom.

Skil tools are low end. They meet a price point for the infrequent user and as in all battery drills, the battery is the first thing to go and can be very expensive. On more expensive tools with better batteries, they can be rebuilt and be more cost effective. Any of the "pro" models will cost from $150 to $300. The Ridgid line is supposed to be good on the lower end. Ryobi is cheap and batteries are about $25. If you want the best, look at Panasonic, Bosch, Festool.

[m Ransley]

12 v is12 v you wont hurt anything , amperage is power used and capacity. If it is 12v nicad . 12v nicads are dead at 12v, fully charged at 13.5 per cell. So if it is a 10 cell 1.2v pack 12v is dead.and drill will be slow at 12v. Fully charged car batteries are apx 13.4v, so keep battry charged and it will work fine. The original battery operated drill had a separate pack, A fuse wont be necessary except for shorted wiring. You could probably run it at 16 v or more. and not hurt anything.

[Jimi Hendrix]

the person who wrote this needs to enroll in a basic electricity class

too much amperage capacity in the voltage source will not fry anything, a device will only pull what it needs based on the resistance of the drill or whatever

he could hook up his drill to an industrial battery that is the size of a house, that is rated at 12V and 1 million amps, and it would not hurt the drill

a shorted drill is a different matter, it should be thrown away, a fuse can protect a short device from melting etc., but shorts are exceeding rare in cordless drill anyway

[anoldfart2]

Thanks for all replies. I agree on the fuse. I know the lighter socket is fused, but if I use that gel-cell I will need a fuse. Does anyone have any idea of the amperage draw on these drills?

Yes, I know Skil is crap. But I got the thing so I may as well use it till its dead. Having a drill in the car is sort of handy actually. One never knows when they might get a toothache while travelling. ---- Drill out tooth, fill with Bondo ----

[Pop]

Uhhhh, NO! What school did you go to? The current depends on the VOLTAGE, especially in the DC world. A car battery, with the exception of a fault like putting an accidental short on it across the drill wires somehow, would

99.999% sure work fine both with and without the engine running. A 1 ton 12V battery would work, too. You'd want to be certain there could be no way to put a short across the car battery, but that's easy to do.

Please quit guessing and rationalizing; it doesn't become you.

Pop

[Ralph Mowery]

That was my first thought, but with motors, the motor will generate a back EMF and if it is not turning fast enough, it will burn out. The rechargables will not usually be able to put out enough current long enough for this to hapen. Hooked to a car battery with a capacity of a few hundred amps and the drill could burn out very quick in a stalled situation.

[Rich256]

Coreect. I have an old one that I do it with all the time. Just be careful not to stall. If it starts to slow down back off. I have approached stall many times without any trouble.

I don't know if the cigarette plug is adequate. I clamp it to the battery terminals.

[George E. Cawthon]

The replys you are getting are nuts. Sure you can use a 12 volt battery, will work perfect as long as you use the right wire. That drill can draw a lot of amperage so you need to connect directly to the battery. You should not be using wire smaller than #6. Battery cables may be big enough but you still need to keep the length fairly short. There is a reason the lugs on the drill batteries are heavy and that the batteries are attached to directly to the drill.

Try it with not less than battery cables and feel the cables for a temperature rise.

[George E. Cawthon]

One correction. a fully charged battery is 12.6V to 12.7V at 80 degrees. The charge voltage to keep a battery fully charged is 13.4V

[Rich256]

I really don't see that a wire that heavy is not needed They don't draw that much current. Nuber 10 should be more than adequate. Even a 20 foot long wire (total of 40 feet) would have a resistance of 0.025 ohms. So it would take almost 50 amps to get one volt of drop. I am using about a 14 gauge which works fine.

However, stalling is a problem with DC motors. When stalled the back emf drops and it is possible to burn them out.

[JohnR66]

That is correct, but some devices are designed to operate correctly and safely by the power source's internal resitance. Since Ni-Cd batteries have a low resistance, the car battery may be safe. The drill may not deliver max torque due to the loss in the wires. Use a heavier cable if distance is great. John

[RicodJour]

Could, don't know why you'd want to do it, though. It would have the worst features of a cordless and a corded drill. Probably time to shop for a new one.

R

[m Ransley]

George do you mean lead acid is fully charged at 12.7 at 80f. I have one rated for more but maybe 12.7 is the correct average, Nicads do peak at

1.32-1.35.

[m Ransley]

You dont need real heavy wire 14 ga works fine, you wont get voltage drop that will matter or hurt anything. On high amp draw RC cars I have a 30 amp fuse is used but not because of motor damage but speed control damage, which the drill has in the trigger VS. Here stalling with high amp could fry a cheap or old drill since high amp was not in its design. Safe would likely be 10a for a 12v drill. My new makita has a curcuit that shuts down the drill and resets on stall surge. My old Makita doesnt, Use a fuse and dont stall it, But drilling metal is hard not to stall the drill. Maybe wire in an inline auto type fuse, experiment, start with 5a, New RC controlers can handle 100a, but cheap drill are cheap and built to the packs limitations. A 7 cell 1200ma can blow a 30a fuse stalled. A good motor will just get real hot, but a cheap drill who knows, Fusing is the only way to protect it, Any RC shop will know the proper amp fuse.

[Rich256]

12.65 volts is 100%

Section 4.4