Popular Woodworking 2002-10 № 130, страница 40
12-VOLTi i Cordless drills are now a ubiquitous part of most workshops. Offering good performance for a vast number of drilling and screwing tasks, they also offer maximum freedom and flexibility. We consider 12-volt models to be the best balance of weight, size and performance for a home shop. Certainly there are applications for smaller and larger voltage units; but in general, 12 volts is just right. If you have a job requiring extraordinary torque, an 18- or 24-volt tool will handle the task, but it'll cost you in the wallet and the wrist. SETUP & USE Basic Use A cordless drill is an easy tool to master. Most offer two speed settings, with the lower speed providing greater torque and better control for driving screws. The higher speed setting is better for drilling holes, where torque is not as critical. First, a tip on how to hold a cordless drill: Don't use your trigger finger to pull the drill's trigger. Use your middle finger to squeeze the trigger and your index HANDLES T-shaped handles offer better balance (the drill will stand upright on your bench), while pistol-grip handles let you to apply more pressure behind the tool. TORQUE Torque is force, not speed. Higher torque occurs at lower speeds. The higher the torque rating, the better. BATTERIES Batteries are rated in amp-hours, with more amp hours equivalent to longer time between charges. Nickel Cadmium (NiCad) batteries are most common. Nickel Metal Hydride (NiMH) batteries are reported to offer longer run-time, but not all manufacturers agree to their benefit. Get two batteries whenever possible. SPEEDS A two- or three-speed gearbox improves the balance between torque and speed, offering better performance options.Variable speed is a benefit in addition to multiple speeds, allowing the user to control the speed of the drill for delicate operations. CLUTCHES Clutches disengage the motor when a set torque resistance is achieved, keeping you from stripping the heads off screws. Clutches are useful, but 24 settings aren't necessary. If the tool has more than 10, you're fine. CHUCKS Keyless chucks make bit changing an easy, tool-free operation. Single-sleeve keyless chucks operate with a shaft brake that allows true one-hand operation.The best chucks offer metal jaws that close tight enough to hold a 1/i6" drill bit. CHARGERS One-hour chargers are standard, but some faster chargers are included as an upgrade. Three-hour chargers still exist but only on economy models. Look for the trickle charge feature; it keeps the battery fresh. finger to point where you are drilling. When you start to drill a hole, pay attention to the drill bit's angle to the wood in both the front-to-back and left-to-right orientation. If you learn to align the drill correctly in these two axes, it's easy to drill a straight hole. If you buy a drill with a bubble level, it can help drill a straight hole, but you may end up spending all your time staring at the level, and not getting very far with your project. When drilling completely through a piece of wood, the force of the bit exiting the back of the wood will push the wood fibers out of the way rather than cut them. This is blow-out. To avoid it, place a scrap piece of wood directly beneath or behind your good piece. The bit will continue to cut into the scrap piece, leaving a clean exit hole. Phillips screws (with the "+" head) are easier to install than slotted, but square-drive or the similar Robertson-drive screws are even easier, locking the bit into the screw head so it can't slip out unless really forced. When choosing the type of drill bits to use, consider what you're drilling into. Brad point, or bullet-point drill bits have a smaller diameter "starter" tip that keeps the bit from wandering and are easier to align dead-center on a mark. Twist bits don't have the starter tip and will work well in wood also, but they're less efficient and user friendly. For larger holes (over 1/2" in diameter), spade or Forstner bits provide better cutting performance. PW PW Recommends OCCASIONAL USER • Hitachi FDS12DVA A bargain 12-volt drill ($130) that provides lots of features with a little less torque - and they throw in a useful flashlight! • Ryobi HP1202MK2 Ryobi's drill offers all the features an occasional user will need, and more, at a good value ($60). SERIOUS, ADVANCED OR PROFESSIONAL WOODWORKER Competition is tough in this category so most manufacturers have to offer quality tools, meaning it's hard to go wrong with any brand name tool. Any of those listed below will give you years of quality service. • Bosch 32612 ($130) • DeWalt DW980K-2XRP ($180) • Metabo BST12 Impuls ($170) • Milwaukee 0502-23 ($145) • Makita 6217DWDE ($170) • Panasonic EY6407NQKW ($180) • Porter-Cable 9866 ($140) The DeWalt drill offers a third gear speed for better torque-to-speed ratio, while the Metabo offers a pulsing setting that improves torque control in short bursts. The Panasonic deserves mention for its quality, durability and top-rate battery technology. These tools have been tested or used by the editors of Popular Woodworking and have earned their recommendation. 40 Popular Woodworking October 2002 |
