Chuck & Clutch
Chuck. Keyless chucks have seen some serious advances in recent years. Milwaukee, Porter-Cable, Bosch, DeWalt, Metabo, Hilti, Craftsman, and Panasonic have chucks that easily ratchet down and lock onto the bit. This means no more burned palms from cranking the chuck to insert or remove a bit. Bits don't jam nearly as easily, either. The Hitachi and Makita models still use older designs that don't tighten and release as surely, and this resulted in some bits jamming during the high-speed drilling test.
Plastic chucks can cause problems, too. I've cut raised grooves into several of them by inadvertently drilling too close to a proud nail head or hunk of metal. The grooves are sharp and make tightening the chuck downright painful. The all-metal Milwaukee and Porter-Cable chucks--the only all-metal, ratcheting/locking chucks in the test--won't have this problem and seem indestructible. The Bosch, DeWalt, Craftsman, Panasonic, Hilti, and Metabo drills all have ratcheting/locking chucks, but they aren't all metal, they're a plastic/metal combination. The Makita and Hitachi chucks are mostly plastic.
Clutch. All the drills have a multi-position clutch ranging from 16 positions (DeWalt) to 22 (Hitachi). Personally I don't see the need for more than six positions. The Makita requires you to press a tiny button to bypass the clutch for the drill position on the clutch dial. It wasn't easy to use barehanded and was impossible to use with gloves on. Hilti's black-on-black clutch settings are almost impossible to see.
Drilling Capacity: High and Low Speed
For drilling shallow holes, I use spade bits and set my drills at high speed for fast cutting. For deeper holes in double and triple studs or joists, the tool needs more low-end torque to power through the material and evacuate chips from the hole. For these holes, I switch to an auger bit and set the tool to low speed.
To determine each tool's drilling capacity in both speeds, I put a new bit on each tool and drilled until the battery's power delivery trailed off. In high speed I drilled holes in a single 2x4 stud with a 1-inch spade bit. For the low-speed test, I drilled through a double 2x4 with a 15/16-inch auger bit. Each time I looked for the tool that drilled the most holes on a single charge.
High Speed, Single 2x4. The 18-volt tools rule the roost for number of holes drilled. The Bosch drilled so many holes--79--I couldn't believe it, so I recounted them. The Milwaukee tore through 89 holes and I wondered if its battery was nuclear instead of Nicad. Porter-Cable's 19.2-volt drill, at 74 holes, did great too. Each of these tools cut quickly and smoothly, and they didn't feel like they were jumping out of my hand when the going got rough.
The DeWalt drilled 68 holes but was the fastest of the group. Makita came in close behind at 64. The Craftsman made it through 56, and Metabo's bottomed out at 50. The Panasonic tool, at 15.6 volts, drilled 45 holes, but heated up noticeably. Hilti's 15.6-volt tool drilled 43 holes, and Hitachi's 18 volter knocked out 39 holes.
During this portion of the test, it became clear that the DeWalt model is geared not just for high speed, but for really high speed. No drill got close to this tool's 2,000 rpms, which makes a world of difference on site. The rest of the tools' top ends range between 1,400 and 1,700 rpms; the Bosch is the slowest at 1,300 top-end rpms.
Low Speed, Double 2x4. When you need less speed and more torque for deeper holes in doubled- or tripled-up framing, these drills still deliver. This time, the Bosch sunk 40 holes while the Porter-Cable, Milwaukee, Makita, and Metabo sunk 36, showing great low-end torque. DeWalt muscled 34 and Craftsman 32. The 15.6-volt Panasonic and Hilti models delivered 29. Hitachi's tool drilled 20 holes.