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 Cordless Drill Hand Crank 
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Post Cordless Drill Hand Crank
YES I realize the source but found it from another link searching something totally different and thought hmmm this is actually not a bad idea so I thought I wold share it...
All credit to the website below!

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Modified Cordless electric drill: If one takes out the variable speed trigger switch and uses a diode (one way flow device) in series with the permanent magnet motor then we have a unit that can stay hooked up to a battery without acting like a motor. When one cranks, it charges the battery. This becomes a dedicated one direction DC generator without the added losses of the small amount of resistance of the variable speed trigger switch. The following items can be removed from the 14.4 Volt drill.

The white wire from the PM motor is positive when cranked counter clockwise facing the chuck and negative when cranked clockwise for the 14.4 Volt drill. There is also an internal 3 wire component (transistor or SRC I don't know which) that has a heat sink that can sometimes be rewired to act as a diode. Do this in a pinch or emergency, not recommend using if you have a diode available. A diode will work more reliably. For the 14.4 volt drill this 3 wire component will flow in one direction when the black wire is hooked to a positive source (the motor-generator) and the white is negative. I found this component will not work for the 12 and 18 volt drills as a diode. Sometimes it blocks the flow and sometimes is does not block the flow (unreliable).

Use a 4-6 cell battery and check current flow of this 3 wire component in the blocked direction. This back flow test should be well below one ma. If it is not, then use a rectifier diode from another source (junk parts). Otherwise your batteries will slowly discharge, if left hooked up and not turning. For this 3 wire component I found for the 14.4 volt drill and clockwise cranking to hook black to black. For counter clockwise cranking hook white motor lead to black diode lead. Note that the blue wire is not used and is left disconnected but taped up with electrical tape so it will not short to anything

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A diode must be used with the 12 and 18 volt units. When turning the chuck clockwise facing the 12 volt drill then the black lead from the motor is positive and red is negative. Note that one can use say 4 three amp diodes in parallel if that is all one can find. For the parts taken out of the 12 volt drill and the end result see the photo on the left. The following is the basic circuit of how to hook up a cordless drill to charge a single cell. Notice that no switch is needed. This will be true as long as the reverse flow on the diode chosen is very low. The amp and volt meter are for testing once satisfied all will work ok they can be removed from the circuit as in the photo on the right.

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The crank can be made from an 11" long by 3/8" diameter plated treaded rod. Bend at 1" and to make a 5" cranking radius. The rest of the length becomes the handle. Make your bends gentle and not too sharp or it will break. Find a chunk of round wood (closet coat hanger dowel is about right) and drill a 3/8" hole through the middle of it. Slip over the shaft and put a nut on it with lock tight or epoxy in the threads (to make it stay in a permanent location). I also tested a 3/8" ID rubber hose as a handle but didn't like it as much as a bigger diameter wood approach. Optional: Sand or file a flat on three sides of the 3/8" threaded rod to keep it from coming loose easily in the chuck of the drill. I experimented with different radiuses and handles. The one that worked the best for me is the one with the round wood dowel handle at a 5 inch radius. These are the wooden handle ones in the picture.

The 12 volt and 14. 4 volt hand crank modified drill generator weighs about 2 lb 2 Oz with the lead wires and clips. The crank is about 6-7 Oz. Total weight is about 2.5 lbs. What to do with the battery packs that come with and plugs into the drill. This now becomes a source of single cell batteries that can be individual charged. One takes the cover off and attaches a wire to each end of each cell without taking the series string apart. These wires are run to the outside of the case where the alligator clips from the drill generator can be used to charge each cell individually. Then depending on the voltage needed to run the intended device one can tap off the voltage needed. Another way is to break them into individual cells charge them separately and rewire temporally back into a series to get the voltage necessary to run radios or lights.

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Output test results of hand cranking One Cordless Drill.

Comfortable Hand crank speed is about 80-90 RPM (normal cranking). High speed is about 1.5 to 2 times that speed.

12 volt red drill charging one cell: (.5 to 3 watts)
Fast cranking open circuit 4.1 volts max and 1 to 2 amps at 2 volts or an average 1.5 amp x 2 volts = 3 watts. Normal Cranking produces .2 to ..5 amps at 1.5 volts or an average of .35 amp x 1.5 volts = .5 watts.

14.4 volt drill charging one cell: (2.2 to 5.7 watts)
Fast cranking open circuit 5.4 volts max and 2.5 to 3.5 amps at 1.9 volts or an average 3 amp x 1.9 volts = 5.7 watts. Normal Cranking produces 1.1 to 1.6 amps at 1.6 volts or an average of 1.35 amp x 1.6 volts = 2.2 watts.

14.4 volt drill charging two cells in series: (1.2 to 4.2 watts)
Fast cranking open circuit 5.4 volts max and 1.2 to 1.5 amps at 3.1 volts or an average 1.35 amp x 3.1 volts = 4.2 watts. Normal Cranking produces .3 to .6 amps at 2.75 volts or an average of .45 amp x 2.75 volts = 1.2 watts.

18 volt drill charging one cell: (1.8 to 4.8 watts)
Fast cranking open circuit 3.9 volts max and 2 to 3 amps at 1.9 volts or an average 2.5 amp x 1.9 volts = 4.8 watts. Normal Cranking produces .9 to 1.4 amps at 1.6 volts or an average of 1.15 amp x 1.6 volts = 1.8 watts.

Summary: Hand cranked cordless drills can be converted to generate a small amount of electricity in an emergency. Expect to charge a one cell at about 1 to 3.5 amps or 2 to 5 watts. For each watt of power generated for one minute (1 watt-minute) will run one white LED for 15 minutes. Thus 5 watts generated for one minute theoretically could result in 75 min run time for one LED. In practice one would need to charge 3 separate cells to get the necessary voltage to run one LED. The cells could be charged all at once in parallel then rearranged in different battery holders to be wired in series to run the LED(s) or charge each cell separately while staying connected in series. Bottom line: In an emergency one could crank out enough power to keep a night or task LED light going while it is needed.

http://www.zetatalk.com/energy/tengy05p.htm

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Mon Jun 07, 2010 6:59 pm
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Post Re: Cordless Drill Hand Crank
Rules of thumb or lessons learned from current experience:

When generating optimum maximum output power plan on an output voltage of no higher than half the drills rated input voltage. Use 2 drills in series when planning to generate near to the rated input voltage for the given drills.
I don't recommend running any unit faster than it was designed to run originally. Rated speed for 12 volt unit is 500 RPM, 14.4 volt unit is 550 RPM, and 18 volt unit is 900 RPM. I have noted that one gets about 80 percentage of the input voltage as output open circuit voltage when acting as a generator at rated maximum speed. Use this as a guide to make sure your design doesn't end up going too fast.
It's hard to say what the maximum sustained current capability of these units is. My best current guess is about 3-4 amps for 12 volt, 3-4 amps for 14.4 volt and 4-5 amps for the 18 volt unit. The short term surge max can be twice the current in the previous sentence. Plan on using no higher sustained output power than 13, 22, and 41 watts for 12, 14.4 and 18 volt tested individual drills.
Turning the unit at faster than rated speed could ware out the gears and bushings before there time and is not recommended. The electrical components are not designed for voltage much above the rated input voltage. Also, there is a strong possibility of thoroughing a bar on the commentator of the motor due to centrifugal force and heat. This happened on one test run where it was generating into a heavy load at more than twice the rated voltage.
Output efficiency is about 30 to 40 percent of input power. The rest of the input power goes to gear friction and electrical losses as heat.
The 14.4 volt cordless drill is the current best unit for hand cranking because of it's higher efficiency and high volts/RPM ratio. This would hold true for water power also. For bicycle pedal powered cranking the 14.4 volt and 18 volt both will work. I favor slightly the 14.4 volt unit however the 18 volt unit might just make up for this by lasting longer.
On the bicycle generator if you find the power wildly surging with every half turn of the pedals, then chances are the drill drive wheel is too small and the pedaling needs to be made easier. One can also add weight or make a flywheel effect out of the bicycle wheel but this is not recommended due to possibly causing other things to ware out quicker.
For bike and water wheel applications feel the temperature of the generator from time to time by sticking your finger into the open slot where the trigger switch was to feel the metal case of the motor. Cut down on your output power if it is getting hot. The estimated maximum allowable power output for the 2 drill series combination is twice the above recommendation or 26, 44, and 82 watts.
Be sure to use a one way rectifier diode in series with the unmodified cordless drill when taping closed the trigger switch to make a DC generator. Use a diode in preference to converting the internal 3 wire component to a diode. I don't have much trust in this component.

http://www.zetatalk.com/energy/tengy05o.htm

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Mon Jun 07, 2010 7:00 pm
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Post Re: Cordless Drill Hand Crank
In looking for the efficiency and maximum voltage and power available from cordless drills used as DC generators the following measurements were preformed. One drill was powered to turning another of the same type hooked up as a generator. There was a short bolt put in the chuck of each unit to mechanically tie them together. Both were turning at the same speed. Several conditions were measured. The input current and voltage used under no load as a single drill was measured. The input current and voltage was measured while tuning another drill under no load was measured. Then the input current and voltage was measured while tuning another drill while generating output power was measured. From these measurements the efficiency of each type of unit was then determined. See the table below for a summary of the average measurements and calculated results.

Type of # of Input Input Input Output Output Output
Tests Drills volts Current Power Volts Current power
12 volt drill 500 rpm max 3 cells
Off OC 0.00
13.37
0.00
0.00
4.10
0.00
0.00

No load 1.00
12.30
1.65
20.23
0.00
0.00
0.00

Open Circuit 2.00
11.87
3.60
42.68
8.73
0.00
0.00

Generating 2.00
11.05
7.42
81.99
5.32
2.50
13.30

14 Volt drill 550 rpm max 4 Cells
Off OC 0.00
15.46
0.00
0.00
5.46
0.00
0.00

No load 1.00
15.50
1.17
18.14
0.00
0.00

Open Circuit 2.00
14.26
2.14
30.52
11.40
0.00
0.00

Generating 2.00
12.75
6.94
88.42
7.09
3.13
22.16

18 Volt drill 900 rpm max 4 Cells
Off OC 0.00
20.20
0.00
0.00
5.46
0.00
0.00

No load 1.00
19.20
1.81
34.75
0.00
0.00

Open Circuit 2.00
18.60
4.81
89.47
15.40
0.00
0.00

Generating 2.00
17.25
11.89
205.10
8.12
5.1
41.62


Output Power Percentages
Power Losses Results and Description
12 volt drill 20.97
0.44
average /drill gear train power loss
13.37
0.28
average /drill electrical power loss
0.28
efficiency generating at max speed
14.4 Volt drill 16.22
0.29
average /drill gear train power loss
16.92
0.3
average /drill electrical power loss
0.40
efficiency generating at max speed
18 Volt drill 41.41
0.34
average /drill gear train power loss
40.34
0.33
average /drill electrical power loss
0.34
efficiency generating at max speed

Summary of the results:
12, 14.4, and 18 Volt drills at rated speed output a maximum of 8.7, 11.4, and 15.4 open circuit Volts. This is to say the output voltage is roughly 74, 80, and 83 percent of the input volts when acting as a motor generator set. The suggested maximum rated output generated power at rated speeds of 500, 550, and 900 is 13.3, 22.2, and 41.6 watts. The electrical output generating efficiency is about 28, 40 and 34 percentage of the total input power. This to say that the 14.4 Volt drill is slightly more efficient at generating power than the other two.

http://www.zetatalk.com/energy/tengy05m.htm

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Mon Jun 07, 2010 7:01 pm
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