You probably already know this but thought I'd bring it up since it wasn't mentioned. When it comes to batteries, there are several chemistries they use. They are Ni-cad, Nimh, and Lithium ion. It is my understanding Ni-cad batteries are still used on most tools. However, they can be a problem, especially if you don't maintain them correctly. If you charge them without running them down completely, they will develop a memory. That translates to the battery will not discharge all the way. Example, you take the battery to 50% capacity. You then charge it. Now, you will only get 50% of the battery capacity before the battery dies. This may not happen immediately, but over time if the pattern continues, it will. Also, Ni-cad batteries will loose their charge when not in use. So if you are like me and don't use your tools for a couple months, you should plan on charging the battery when you do need them. Finally, Ni-cad batteries are the heaviest. Nimh batteries are better in that they are not supposed to develop a memory. They do loose their charge over time, though and are also sensitive to overcharging. You will need a charger that is designed for these types of batteries. Don't use a charger designed for Ni-cad batteries to charge a Nimh battery or you could run into problems. Lithium ion batteries are the lightest and best when it comes down to it, but they are more expensive. They don't have the memory problems of Ni-cad. They will not loose their charge as fast as Ni-cad or Nimh. It is my understanding they can go for months on end in storage and have close to a full charge. A Lithium ion is smaller but can have more power than the Nimh or Ni-cad equivalents. I personally have Rigid tools and recently got a compact cordless drill which came with 2 Lithium ion batteries. These batteries are 3 mah. The batteries that came with the original tool kit are 2.5 mah, over twice as big, and more than twice as heavy. Another advantage to Lithium ion is that you will get full power up till the last drop of energy is used, which can't be said for Nimh or Ni-cad batteries. Again, make sure the charger you use will charge Lithium ion batteries. It is my understanding these batteries can be particularly nasty if you use the wrong charger. Speaking of chargers, the ultimate would be one that could do all types of batteries mentioned here. Assuming such a charger exists, and assuming it is available for your tools, this would be something worth looking into.
Shane ----- Original Message ----- From: Ray Boyce To: blindhandyman@yahoogroups.com Sent: Tuesday, February 05, 2008 11:43 PM Subject: [BlindHandyMan] How to Choose a Cordless Drill for Woodworking With advances in technology in recent years, cordless drills are a popular and viable choice for nearly all hand held drilling tasks on almost any woodworking project. Cordless drills come in various sizes and with a number of different features. What features should you look for when buying a cordless drill? Begin With the Battery: When looking for a cordless drill to meet your woodworking needs, the first thing to consider is the battery. Cordless drills are presently available in voltages from 9.6 volts all the way up to 24 volts. The advantage of a more powerful battery translates to additional torque for driving long screws into stronger hardwoods. It also likely means longer battery life per charge. However, these stronger batteries also mean a considerably heavier drill. A 24-volt cordless drill is much heavier than a 12-volt cordless drill, and considerably heavier than a corded power drill. Mandatory Features: Any cordless drill that you should consider for your woodworking projects should have a number of basic features. These include a reversible motor that will allow you to back out any screws that you drill in, a dual-speed motor (with a high and low switch) and an adjustable clutch, that, when adjusted properly, will help keep you from driving screws too deeply into your wood stock. Additional Features to Consider: Many cordless drills use a 3/8" chuck to hold your bits. However, some larger models have a 1/2" chuck that will allow one to use drill bits of up to 1/2" in diameter. These 1/2" models often include a "hammer drill" feature which has little practical application for woodworking, but is great for drilling holes in masonry. Many recent cordless drill models employ a "smart charger" that will help extend battery life by optimizing the way the batteries are charged. On these chargers, when the battery is approaching a "full" charge, the charger switches to a trickle-charge mode until the battery is maxed. Many models will also include two batteries with the drill and charger, which, while it is not a requirement, is certainly a good idea. With two batteries, you can be using one and charging the other at the same time. How to Choose: Ironically, a great many of the cordless drills available on the market have all of the features we've already discussed. What, then, should you look for to differentiate between these models? In my mind, there are two major factors to consider when all else is equal. First, when you look at the batteries, look beyond the voltage. For instance, all 12-volt batteries are not the same. When comparing batteries of the same voltage, the battery with a higher mAh rating (which stands for milliamp-hours) will hold a charge for a longer period of time. The other factor to consider comes into play when you pick up the drill with the battery installed. Hold the drill in a number of positions, including over your head, as if you were drilling screws into your ceiling. Ask yourself questions like, "How does this drill feel?" "Is it balanced?" "How long could I use this drill holding it over my head?" If the drill is simply too heavy to comfortably use over your head for at least 30 seconds at a time, then you likely need to look at a drill with a lower battery voltage (and hence, a smaller size). The drill should be strong, but comfortable to use. The bottom line is, if you don't find your drill comfortable, then you won't enjoy using it. Find one that feels good in your hand and you'll be more likely to put it to good use on all of your woodworking projects. ------------------------------------------------------------------------------ No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.19.20/1261 - Release Date: 2/5/2008 8:57 PM [Non-text portions of this message have been removed]
