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Harbor Freight 7.2v Drill

With the apparent demise of the popular "Handiwork" 4.8v drills from Walmart this drill may be its natural successor for weight concious 12lbers. Its the  Harbor Freight #3504 7.2v Drill. Its spec'd at 400rpm at 7.2v.

The battery pack uncips of the bottom of the drill just like on the bigger versions. There is no clutch.

The case comes apart after removing nine phillips screws and then the motor/Gearbox with the chuck still attached can be lifted out after cutting the wires.

The chuck is removed by first undoing the LEFT hand drive screw that is inside the chuck. Turn this one clockwise to loosen and remove (keep it for later use).  Then with the gearbox lightly clamped, put a spanner on the flat section of the shaft (I used 13mm, but half inch may fit) and give the other end of the spanner a sharp tap with a hammer in an anti clockwise  direction. This will loosen the chuck on its conventional right hand thread and it can then be unscrewed and removed. Put the Left hand thread screw back on the gearbox so you don't lose it!

The battery comes apart easily by removing a few more screws and contains six AA type Ni-Cads. They might be useful for something....

Here you can see the 12v and 7.2v versions side by side. the 7.2v has no clutch (the big outside gear has cast-in "bumps" that lock it in place much as the way  the added screws do it the bigger drills. Otherwise the gear casing looks identical. The output shaft on the 7.2v is slightly shorter  though and has a couple of flats on it. The motor is made by the  same company but is much smaller than its 12v cousin. The whole assembly weighs about 3oz less.

I don't have a plan for these motor/gearboxes yet but four of them might do well in a 12lber when run at 12v.