| If you were a professional contractor who used | | | | "hammers" on the bit in a lateral direction along |
| various types of drills on a daily basis throughout | | | | the length of the bit as it rotates where an |
| the course of your job, you would probably | | | | impact driver impacts the chuck of the drill in a |
| already know what type of drill you need for a | | | | rotational direction. The result is a huge increase in |
| specific job. But, what about the person who | | | | torque. The impact action also causes the screw |
| does not work with drills every day. This person | | | | bit to grab the screw resulting in less slippage, |
| probably knows that a certain job or task | | | | reducing the possibility of stripping the screw |
| requires the use of a drill, but may not be certain | | | | head. As an added bonus the amount of force |
| about what type of drill is needed. Choosing the | | | | the operator needs to apply to the drill in order to |
| right drill can be a daunting task and it's really no | | | | keep the screw bit from slipping is significantly |
| surprise with all the types of drills to choose from. | | | | reduced resulting in less user fatigue. |
| You have: | | | | Impact drivers have a quick change bit holder |
| - basic drills | | | | designed for accepting hex shank bits which are |
| - VSR drills | | | | now common among screw bits and many other |
| - drill/drivers | | | | drill bits and socket driver bits. This style bit holder |
| - hammer drills | | | | really makes changing between bits a snap. This |
| - impact drivers/wrenches | | | | bit holder is the main difference between an |
| - rotary hammer drills | | | | impact driver and impact wrench. An impact |
| - right angle drills | | | | wrench has a square drive for accepting either 3 |
| - spade handle drills | | | | 8" or 1/2" drive sockets depending on the model |
| Maybe you have already been looking at drills and | | | | of impact wrench. |
| have other questions such as: | | | | Impact drivers and wrenches also have a size |
| - What does VSR mean? | | | | advantage delivering as much as 4 times as much |
| - What is the difference between SDS and spline | | | | torque as a comparable size VSR drill. This means |
| drive? | | | | that a smaller size tool can be used for a |
| - How does chuck size matter? | | | | particular job which further reduces user fatigue, |
| - What is the difference between keyed and | | | | especially when working overhead. The small size |
| keyless chucks? | | | | also gives you the ability to work in tighter spaces |
| - What is a hex driver? | | | | and if the impact driver uses lithium-ion |
| - Should I go with a cordless or corded drill? | | | | technology, then the tool weight is even further |
| - What type of cordless battery is best? | | | | reduced. |
| - What is the clutch used for? | | | | There is one particular impact driver that stands |
| Many years ago, when the first hand held power | | | | out. In a tool test by Tools of the Trade |
| drills came around, there were not many choices | | | | Magazine, out of 9 top of the line cordless impact |
| outside of brand names when it came to selecting | | | | drivers, the Milwaukee 9081-22 was able to |
| a power drill. Basically, the drills were all corded, all | | | | outrun the group when pushed to the max. This |
| had keyed chucks, and rotated in only one | | | | tool sent 48 4" long Timberlock screws into the |
| direction and at one speed. So, the choice was | | | | stock before a noticeable battery slowdown was |
| not too difficult. Just pick a brand you like. | | | | observed. Timberlock screws are a long screw |
| Things certainly have changed over the years. | | | | with a hex head. They are commonly used in |
| There are enough options available today to | | | | outdoor applications such as landscaping, fence |
| make a person's head spin. There are even more | | | | and deck building because they require no |
| variations and innovations in the works as I write | | | | pre-drilling. Just think of the time you could save |
| this. While the scope of this guide will not be able | | | | when armed with an impact driver and screws |
| to cover every type of power drill in existence, | | | | that require no pre-drilling. |
| we are going to try to cover most of the bases. | | | | Right Angle Drills |
| My goal in writing this article is to help those who | | | | Right angle drills, as the name implies, have the |
| might be having difficulty deciding which type of | | | | chuck positioned at a right angle to the body of |
| drill they need, so let's get started. | | | | the drill. Right angle drills are able to drill in tight |
| The basic corded drill | | | | spaces where other drills just won't reach such as |
| This is the most basic of hand held power drills. It | | | | in between two closely positioned wall studs which |
| is a simple electric drill with one speed and one | | | | makes these drills particularly useful for plumbers |
| direction. It is mainly good for drilling holes in | | | | and electricians. |
| wood, metal, plastic, and soft metals. It is not the | | | | These drills come in both corded and cordless |
| ideal choice of drill to use for applications such as | | | | varieties as well as a wide range of sizes. The |
| driving screws. Since the speed is not variable and | | | | smaller size right angle drills are suitable for small |
| the drill only operates at a higher RPM, you would | | | | to medium jobs in pine and other soft material. |
| likely either strip the screw head or snap the head | | | | The heavy duty models can handle much larger |
| off the screw if you tried. You will not likely find | | | | jobs in harder material such as thick oak. One |
| many of these around today as their uses are | | | | thing you should be aware of when using the |
| rather limited. | | | | more powerful heavy duty models is reaction |
| The VSR drill | | | | torque. Due to the design of right angle drills, if |
| VSR stands for "variable speed reversible". These | | | | the bit should get stuck, the entire drill body will |
| drills come in both corded and cordless versions | | | | rotate around the chuck potentially causing injury. |
| as will most all the drills we discuss from here on | | | | It's generally a good idea to brace the drill against |
| out. The drill speed is varied by the amount of | | | | a floor, wall, or stud. Some models have a built in |
| pressure applied to the trigger. The farther the | | | | torque limiter or clutch to help prevent this |
| trigger is pulled, the higher the RPM will be. There | | | | occurrence. One such model which has a built in |
| is also a switch, usually near the trigger which | | | | torque limiter is the Makita DA4031 [ This |
| reverses the operation of the drill. As you can | | | | heavy-duty right angle drill was also the overall |
| imagine, these have distinct advantages over the | | | | winner in a Tools of the Trade test of several |
| basic corded drill. In addition to being able to | | | | top of the line right angle drills. |
| perform all the functions of the basic corded drill, | | | | Spade Handle Drills |
| they also have a better suited although still limited | | | | When spade handle drills are mentioned, one might |
| ability to drive screws, and small lag bolts. Since | | | | likely think of mixing drywall compound. The |
| the speed is variable, you have the ability to drill | | | | mixing of drywall compound or similar substances |
| into harder material without overheating the bit. | | | | is one of the most commonly used applications of |
| One disadvantage to this type of drill is that trying | | | | spade handle drills. These drills are designed with a |
| to maintain a certain RPM with the trigger can be | | | | low rpm, high torque setting that is well suited for |
| very tricky. It takes a certain knack and some | | | | mixing drywall mud. Special drywall mixer |
| getting used to in order to be able to drive | | | | attachments can be inserted into the chuck for |
| screws consistently without stripping the heads, | | | | this purpose. |
| driving the screw too deep, or snapping off the | | | | While these drills are very suitable for mixing |
| screw head. The reversible feature allows you to | | | | drywall mud and other similar substances which |
| remove screws, drive reverse threaded screws, | | | | require mixing, this is certainly not the only use |
| and back out of stock when your drill bit gets | | | | for this type of drill. The aggressive torque these |
| stuck or jammed. | | | | drills produce make them ideal for boring large |
| The VSR drill/driver | | | | holes in wood and other materials using spade |
| The VSR drill/driver has all the capabilities of a | | | | bits, auger bits or hole saws up to as large as 5" |
| standard VSR drill with the added bonus of a | | | | in diameter. |
| lower rpm/higher torque setting. Another feature | | | | Many of these drills have a rocker or similar type |
| generally found on these drills is an adjustable | | | | of switch for rapid switching between forward |
| clutch. These are probably the most common | | | | and reverse which aids in backing out jammed |
| types of everyday use cordless drills you will find | | | | bits as well as mixing drywall mud. In addition, |
| on the market today. The big advantage with the | | | | these drills generally have an auxiliary side handle |
| low rpm/high torque setting is that now you can | | | | as well as a spade handle to aid in tool control. |
| drive screws and lag bolts at the low rpm needed | | | | Questions and answers pertaining to power drills. |
| without having to try to hold the trigger in a | | | | What does VSR mean? |
| certain position. The adjustable clutch will keep | | | | VSR stands for variable speed reversible. Drills |
| you from driving the screw to deep, stripping the | | | | with this feature are able to operate in both |
| screw head, or breaking off the screw head. The | | | | forward and reverse rotation and at variable |
| clutch will also prevent reaction torque which | | | | speeds. Most likely the drill will have a switch or |
| happens when a bit jams or a screw bottoms out | | | | button for switching the rotation from forward to |
| and the drill tries to twist in the opposite direction. | | | | reverse. Generally the speed varies in relation to |
| In addition you also get higher torque at the low | | | | to how far the trigger is pulled. |
| rpm setting that you miss out on when using a | | | | What is the difference between SDS and spline |
| standard VSR drill and higher torque means more | | | | drive? |
| screw driving power. These drills generally have a | | | | SDS and spline drive refer to two types of bit |
| slide switch that you use to switch between the 2 | | | | technology used in rotary hammer drills. There is |
| settings. In the high RPM setting, the drill functions | | | | really no difference in the performance of the |
| exactly like a standard VSR drill. In the low rpm | | | | two types, so the one you choose will simply be |
| high torque setting, the drill becomes an effective | | | | a matter of which type your particular rotary |
| driver for driving screws and small lag bolts. Some | | | | hammer drill requires. There are different sizes of |
| of these drills may have a 3rd intermediate | | | | SDS bits which include SDS, SDS+, and SDSmax. |
| setting that compromises between torque and | | | | Smaller rotary hammer drills will use SDS or |
| speed allowing you to better match the speed | | | | SDS+ bits where the larger rotary hammer drills |
| torque setting to the application. | | | | will use SDSmax or spline drive bits. As the name |
| The VSR hammer drill/driver | | | | implies, spline drive bits have a splined shaft, while |
| Do you need to drill into concrete, stone, or | | | | SDS bits have concave recesses in the shaft. |
| masonry? If, so, then you would want to consider | | | | Why does chuck size matter? |
| a hammer drill. This type of drill uses a hammer | | | | Chuck size basically determines what size drill bit |
| or pounding action as the drill bit rotates. The | | | | you can use based on the size of the drill bit |
| pounding action of the bit is what enables these | | | | shank. With the exception of rotary hammer drills |
| drills to bite into the concrete, stone, or masonry. | | | | and impact drivers/wrenches which use a special |
| If you were to try to use a non-hammer type | | | | type of chuck, most typical hand held drills come |
| drill, you would have a hard time penetrating the | | | | with either a 3/8" or 1/2" chuck. Most of your |
| hardened concrete, stone, or masonry and would | | | | smaller drills will use a 3/8" chuck while the |
| likely overheat the bit or the bit would become | | | | heavy-duty models typically use a 1/2" chuck. You |
| jammed in the material. When drilling into | | | | cannot put a drill bit with a 1/2" shank in a 3/8" |
| concrete, stone, or masonry you will also want to | | | | chuck, but you can put a bit with a 3/8" shank in |
| be sure and use a masonry bit. A masonry bit is | | | | a 1/2" chuck. |
| specially designed for drilling into these materials. | | | | What is the difference between keyed and |
| Depending on the material, the drill and the bit | | | | keyless chucks? |
| used, you can generally expect to be able to | | | | Years ago, all hand held drills used keyed chucks. |
| effectively drill holes in concrete, stone, or | | | | In order to tighten the chuck down on the drill bit, |
| masonry up to around 1/2" in diameter. VSR | | | | you would use a small tool called a chuck key. |
| hammer drill/drivers have all the capabilities of a | | | | Most 3/8" chucks and many 1/2" chucks today |
| VSR drill/driver in addition to functioning as a | | | | are now of the keyless variety. Keyless chucks, |
| hammer drill at the flip of a switch. Due to their | | | | as the name implies, do not use a chuck key. |
| versatility, hammer drill/drivers have become a | | | | Instead the chuck is designed so that a person |
| popular choice among both professional | | | | can easily tighten the chuck down on the bit by |
| contractors and do-it-yourselfers. Some practical | | | | hand. While keyless chucks are faster and easier |
| uses would be, drilling holes for inserting concrete | | | | to use, they cannot clamp down onto the bit as |
| anchors or TapCon screws for attaching fixtures | | | | tight and therefore do not have the same holding |
| such as hand railing or light posts to concrete | | | | power as a keyed chuck. This lack of holding |
| surfaces or attaching fixtures to concrete, block, | | | | power can potentially cause round shank bits to |
| stone, or brick walls. One of the most highly and | | | | slip in the chuck. This is why you will still find many |
| professionally rated hammer drill/drivers on the | | | | heavy-duty high torque drills using keyed chucks. |
| market today is the DeWalt DC925KA. | | | | What is a hex driver? |
| Rotary Hammer Drills | | | | A hex driver is just another name for an impact |
| Think of a rotary hammer drill as a larger, more | | | | driver. Hex refers to the type of bit holder the |
| powerful version of a hammer drill with an added | | | | drill uses. These drills use a hex shank bit designed |
| bonus. It also works like a small jack hammer. | | | | not to slip in the holder. This type of bit holder |
| These drills are dedicated to the purpose of drilling | | | | also makes changing bits a snap. Impact |
| and chipping into concrete, stone and masonry. | | | | wrenches, on the other hand use a square drive |
| They are generally not intended for drilling into | | | | for accepting either 3/8" or 1/2" drive sockets. |
| wood or other similar materials. Rotary hammer | | | | Should I go with a cordless or corded drill? |
| drills use a special bit designed not to slip in the | | | | This can be a difficult decision for some. The |
| chuck. The most common types are the SDS and | | | | industry trend is ever going more and more |
| spline drive. The type of bit you use will depend | | | | towards cordless technology. The very first |
| on the drill. SDS bits come in several different | | | | cordless drills on the market left much to be |
| sizes, so you will need to get the size that | | | | desired in both power and run time. Over the |
| matches your drill. If you want to drill many larger | | | | years cordless technology improved to the point |
| diameter holes in concrete or stone, then this is | | | | where many cordless tools now compete with |
| the type of dill you need. | | | | and even in many cases out perform their corded |
| As mentioned, this drill also functions like a small | | | | counterparts. With power and performance |
| jack hammer. By flipping a switch you can turn | | | | becoming near equal, the choice basically comes |
| off the rotary action, then insert a chisel bit and | | | | down to price. Are you willing to save some |
| you're ready to go. While rotary hammer drills | | | | money and deal with the inconveniences of |
| aren't going to compete with a full sized jack | | | | dragging power cords around, or would you rather |
| hammer, they are very useful for many smaller | | | | spend a little more and have complete freedom |
| jobs such as removing ceramic and stone tile, | | | | of movement? The choice is yours. |
| removing bricks and blocks from existing wall or | | | | What type of cordless battery is best? |
| floor structures, chipping away unwanted or spilled | | | | The power tool industry is currently trending |
| mortar, chipping the rough edges from concrete, | | | | toward lithium-ion battery technology. With all the |
| and removing excess concrete from concrete | | | | benefits of lithium-ion it is easy to see why. If you |
| forms or other surfaces. | | | | compare lithium-ion batteries to nickel cadmium |
| Traditionally, rotary hammer drills were all of the | | | | batteries, lithium-ion charges faster, runs longer, |
| corded variety since cordless batteries were not | | | | maintains longer constant power output, weighs |
| able to supply the power needed to operate a | | | | less and stores a charge longer. The disadvantage |
| rotary hammer drill. However, all that is changing | | | | is that Lithium-ion costs more. However, the |
| with advancements in lithium-ion batteries and | | | | difference in price may not outweigh the |
| power tool design technology. The popularity of | | | | advantages you get in performance and charge |
| cordless rotary hammer drills is growing rapidly. | | | | holding time. |
| Some cordless rotary hammer drills rival, and may | | | | What is the clutch used for? |
| even surpass the performance of their corded | | | | Most drill/drivers and hammer drills have an |
| counterparts. One such example is the Bosch | | | | adjustable clutch. The clutch is typically used when |
| 11536VSR which in an HGTVpro power tool | | | | driving screws, nuts, or lag bolts. The clutch is |
| review was found to drill 1/2" holes in concrete | | | | designed so that once a certain required amount |
| faster than the tool's corded counterpart. | | | | of torque is reached, the clutch will engage and |
| Impact Drivers/Wrenches | | | | cause the rotation of the chuck to slip and stop |
| Impact drivers are quickly becoming a hot item | | | | rotating. There are several reasons for this. One, |
| among contractors and do-it-yourselfers and with | | | | you won't strip the screw head when the bit |
| all the added benefits of an impact driver, it's no | | | | keeps turning. Two, you won't drive the screw |
| wonder. If you drive a lot of long screws, lag | | | | too deep. Three, reaction torque when the screw |
| bolts, or have a lot of nuts and bolts you want to | | | | or nut bottoms out won't twist your wrist. Many |
| assemble quickly and easily, then an impact driver | | | | drills produce enough reaction torque to cause |
| is for you. | | | | bodily harm if the clutch is not used. Many |
| The impact driver functions as a standard VSR | | | | heavy-duty drills capable of producing high |
| drill until the time when extra torque is needed. | | | | amounts of reaction torque have either a |
| That's when the impact action kicks in. Don't | | | | non-adjustable built in clutch or a built in torque |
| confuse this with the hammer action of a | | | | limiter. An finally, the clutch protects the drill |
| hammer drill. The difference is that a hammer drill | | | | motor from damage. |