Choosing a Cordless Drill By Funny Advices
What to look for if you want to buy a good drill/driver or you need a model with more power.
A good drill is essential if you are just learning the basics of simple maintenance or are taking on a second addition to the house. And with cordless model, you can drill holes and drive screws with the same tool and have no problems about finding an outlet near the work to power the drill. The good news: There are hundreds of these drills on the market and their price are now lowering with lowering of the batteries cost. The bad news: There are hundreds of these drills and it is hard to find that which you really need.
Power, Handles, Clutch
Power
Power of cordless drills is measured in battery voltage. The higher voltage means more torque-spinning strength to overcome resistance. Over the last years, battery voltage increased to 18V, and the range of models include 6, 7.2, 9.6, 12, 14.4 and 18V. Today’s cordless drills have enough power to bore big holes in framing lumber and flooring. But the another side of power is weight. A average 9.6V drill’s weight is around 3 1/2 lbs., while an 18V model weighs up to 10 lbs.
Handles
Before cordless drill/drivers arrived, most drills had pistol grips, where the handle is behind the motor like the handle of a gun. But most of today’s cordless models are equipped with a T-handle: The handle base flares to prevent hand slippage and accommodate a battery. Because the battery is centered under the weight and bulk of the motor, a T-handle provides better overall balance, particularly in heavier drills.
Clutch
An adjustable clutch is what separates electric drills from cordless drill/drivers. Located just behind the chuck, the clutch disengages the drive shaft of the drill, making a clicking sound, when a preset level of resistance is reached. The result is that the motor is still turning, but the screwdriver bit isn’t. Why does a drill need a clutch? It gives you control so you don’t strip a screw or overdrive it once it’s snug. It also helps protect the motor when a lot of resistance is met in driving a screw or tightening a bolt. The number of separate clutch settings varies depending on the drill; better drills have at least 24 settings. With that many clutch settings, you can really fine-tune the power a drill delivers. Settings with the lowest numbers are for small screws, higher numbers are for larger screws. Most clutches also have a drill setting, which allows the motor to drive the bit at full power.
Speed
The least expensive drills run at a single speed, but most have two fixed speeds: 300 rpm and 800 rpm. A slide switch or trigger lets you select high or low speed. These drills are ideal for most light-duty operations. The low speed is for driving screws, the high speed for drilling holes.
For more refined carpentry and repair tasks, choose a drill that has the same two-speed switch and a trigger with variable speed control that lets you vary the speed from 0 rpm to the top of each range. And if you do more hole drilling than screwdriving, look for more speed — 1,000 rpm or higher — at the top end.
Batteries and Chargers
Nickel-metal-hydride (NiMH) batteries represent the latest breakthrough in batteries. They’re smaller and run longer than standard nickel-cadmium (Nicad) batteries. NiMH batteries also pose less of a hazard when it comes to disposal than Nicads because they don’t contain any cadmium, which is highly toxic. Makita, Bosch, Hitachi and DeWalt offer NiMH batteries, and other manufacturers will soon produce these power cells too. All cordless drills come with a battery charger, with recharge times ranging from 15 minutes to three hours. But faster isn’t necessarily better. A contractor might depend on fast recharges, but slower recharging isn’t usually a concern at home, especially if you have two batteries. What’s more, there are drawbacks to fast charging. A quick recharge can damage a battery by generating excessive heat, unless it’s a specially designed unit. If you want a speedy recharge, go with a tool from Makita, Hitachi or Panasonic, whose “smart” chargers are equipped with temperature sensors and feedback circuitry that protect batteries. These units provide a charge in as little as nine minutes without battery damage.
What to Look For in a Cordless Drill
· Chuck jaws: Maximum capacity on most drills is 3/8 inches. Some 14.4 and 18V drills can handle 1/2-inch-diameter bits.
· Clutch: More settings give you greater control of the depth screws are driven. Speed-range switch: High is for drilling; low is for driving screws. Look for the widest range between them.
· Forward/reverse switch: Should be easy to operate with your thumb and trigger finger.
· Hand grip: Texture and contour should aid your grip; try out the grip before you buy.
· Voltage: More voltage means more power but also added weight.
· Battery: Two are better than one. New NiMH batteries offer some advantages.
· Trigger: Make sure your index finger fits around it comfortably when gripping drill. Variable speed offers the greatest control.
· Keyless chuck: Hand-turn it to open and close the chuck jaws.