Having a good drill is very important but you also need good drill bits. Needless to say, no drill bit is perfect for all jobs. Knowing what drill bit to use can be difficult to find out. Drill bits are available in numerous forms, material and coatings. What kind of drill bits you need depends on what kind of drilling you are going to do.

Just to make sure that your drill bits are performing optimally, remember some rules of thumb.
– Use slow drilling speed when working with hard material
– Use fast drilling speed when working with soft material
– Lift the drill frequently, to clear the flutes of the drill bit and to increase air flow
– Always let drill bits cool naturally, don’t use water to cool them quickly

Drill bits are made of a lot different material but most of them are made of steel. The cheaper drill bits are generally made of low carbon steel. They are softer than drills bits made of high carbon steel. The low carbon steel drill bits are not suitable for drilling in metal instead they are used for drilling in wood. In order to increase their life span they need to be sharpened regularly. The main advantage of low carbon steel drill bits is low price. High carbon steel bits are more expensive but can be used for both metal and wood drilling.

High Speed Steel (HSS) is a type of tool steel that can withstand high temperatures. This means that HSS drill bits can be used for most materials. HSS drill bits are available with various coating material. Thanks to its superior qualities, HSS drill bits have become the choice of the professionals. Given that HSS bits are cheap, it does not really make sense to buy low carbon steel bits, you don’t save much money.

Other materials used for drill bits include cobalt steel alloys, which is similar to High Speed Steel. The advantage of cobalt is that it is less susceptible to high temperatures than HSS. The main disadvantage is that it is more brittle than HSS. Tungsten carbide is very hard and is suitable for extremely hard materials. Due to high cost and brittleness, they are often used as drill bit tips. Polycrystalline diamond (PCD) is extremely hard and used for drill bits or drill bit tips in special cases there downtime for replacing or sharpening drill bits is extremely expensive, for example in automotive industries.

Numerous coatings exist for drill bits. The cheapest of the most common coatings is black oxide. It provides heat resistance, lubrication and corrosion resistance. Black oxide coating is used to increase the life span of steel drill bits. Titanium nitride, sometimes together with aluminium or carbon, is an extremely hard ceramic material. It is often used to coat HSS bits to increase their life time. Note that it is difficult to sharpen coated drill bits without removing much of the coating.

Screwdrivers have been around for a long time. The basic design has not changed much over the years but nowadays you also have electric screwdrivers. The electric screwdriver makes it more comfortable to work. Even better is the cordless screwdriver, you are not limited by the range of the cord. There are a couple things to keep in mind when buying a cordless screwdriver.

First, how powerful screwdriver do you need? As a rule of thumb, the more powerful driver, the heavier it gets. If you will be working a lot with the screwdriver, a light-weight model is generally the best choice. Note that the powerful impact drivers are brute-force tools. They are very powerful but can’t be used with delicate materials, impact drivers will damage the material. If you have a lot of different projects, you may need more than one cordless driver.

Physical parameters are also important. You should take care of the size of the screwdriver. If your hands are small, a big screwdriver may not be suitable for you. Similarly, if the screwdriver is too heavy for you, you will find it difficult to use it. Apart from size and weight, the shape of the screwdriver should also suit your hands and abilities. These are very small factors but they can create a huge difference, especially when working with the tool for longer periods.

Batteries are another important factor. For heavy duty, you want Li-Ion (Lithium-Ion) batteries. They are more expensive than the older NiCad (Nickel Cadmium) and NiMH (Nickel Metal Hydride) batteries. But they are lighter, have longer lifetime and are more powerful. As a bonus, they have no memory effect. For hobby usage, the older and cheaper batteries are often good enough.

Torque control, meaning that you can adjust rotating force (or turning power) is very useful. Sometimes you need a lot of torque to fasten screws into hard materials but if you work with softer material, you can damage the material if you use too much power. The larger the torque range, the better. If you are working on a wide variety of projects, you need a higher torque range.

Note that all screwdrivers come with reverse action, making it possible to not only to insert screws but also to remove them.

For most jobs around the house, a combined cordless drill and driver is the most cost effective solution. The drill/driver is adequate for most tasks but will be heavier and larger than a cordless screwdriver. Still, if one tool can do two tasks, why buy a second tool.

A cordless drill is a very useful tool. Most modern cordless drills are actually two tools, a drill and a screwdriver. Thanks to the low prices, it is good investment also for non-professional users. The cordless drills have also become lighter and the batteries last longer than a couple of years ago. Even better is that the prices have dropped a lot.

There are a number of things you need to take into consideration when deciding what drill to buy. First you need to answer two basic questions:

–      What are you mainly going to use it for?
–      How often are you going to use it?

Cordless drills come in a number of shapes and sizes nowadays. The most important features are:

Power: Higher voltage batteries give you a more powerful drill but makes the drill larger and heavier.

Battery Life: The higher the Ampere-Hour value, Ah, the longer the battery will last. Note that a high Ah value does not make the drill more powerful, but it will take longer before you need to charge the battery. Generally, a high Ah battery is not heavier than low Ah batteries.

Weight: The more you are using the drill, the more important a light drill is. Holding a drill in the shop is different from holding the same drill in an awkward position. In most cases, a light drill is preferred. If you know that you need a powerful drill, then go for power, otherwise settle for a lighter drill.

Three different types of batteries are used in cordless drills, they are:
– Nickel Cadmium (Ni-Cd)
– Nickel Metal Hydride (Ni-MH)
– Lithium-Ion (Li-Ion)

Nickel Cadmium batteries have been around for a long time. They have a number of disadvantage but they are cheap. Nickel Metal Hydride batteries don’t have some of the shortcomings of Ni-Cd batteries and they are much more environment friendly. But they are more expensive and still have a number of shortcomings. Lithium-Ion batteries are the newest and most expensive batteries. But Li-Ion batteries have a number of advantages, just to mention the most important, lightweight, no memory effect, long lifetime and short charging time. Ni-MH batteries have became less popular, losing out to the cheaper Ni-Cd and superior Li-Ion batteries. Most low-end cordless tools use Ni-Cd batteries while the high-end tools use Li-Ion batteries. Note that Ni-Cd batteries are banned in EU.

If you are going to drill a lot in harder materials, such a concrete, you may want to buy a hammer drill. Hammer drills are heavier and more expensive than standard drills but they add a hammering action, making it easier to drill in hard materials. You can turn off the hammering action when drilling in soft materials. If you are going to use the hammering action a lot, then a corded hammer drill may be a better choice than a cordless model. The hammering actions quickly drains the battery.

Note that with two batteries and a quick charger, you can work non-stop. While you are working the second battery is being charged. Once the first battery is flat, you swap batteries and charge the first battery while you keep on working.

The drill is generally the first power tool people buy. Previously people typically bought a corded drill but lately cordless drills have become more popular than corded models. Cordless drills have a number of advantages. First, it is generally two tools in one, a drill and a screwdriver. Since no cord is needed, a cordless drill can be used almost everywhere. Like many other tools and devices, cordless drills have become more powerful, lighter and cheaper over time. Now it is not just a tool for professionals, thanks to the low prices and its versatility a cordless drill is useful in any household.

It is no accident that cordless tools have become very popular. The main advantage is that they are not limited by the cord, they can be used almost everywhere. Letting you take the tool to the work rather than the work to the tool. Despite the extra weight of the battery, cordless drills are generally lighter than corded models.

Thanks to improved batteries, cordless drills have become both lighter and more powerful. First batteries to be used were rechargeable Nickel-Cadmium (Ni-Cad) batteries. They have a few shortcomings, mainly low capacity and significant memory effect. Ni-Cad batteries were followed by the Nickel-Metal Hydride (Ni-MH) batteries. They offered higher capacity and longer life time compared with the Ni-Cd batteries. The latest type of batteries is the Lithium Ion (Li-ion) batteries. They have no memory effect and are lighter but more powerful than the older types of batteries. Unfortunately, they are also more expensive than Ni-Cad and Ni-MH batteries. Today’s Ni-Cad batteries are in most cases good enough for hobby users. On the other hand, professional usage pretty much requires a double pack of Lithium Ion batteries. The second pack is useful as a spare. You just replace the flat battery pack with the charged spare pack and continue to work, while the first battery pack is being recharged.

In order to use a drill as a screw driver, the drill needs to support variable speed, torque control and reverse drive. Low speed is necessary if you are using a drill as a screwdriver, so variable speed control is a must. Torque control shuts off the drill when a certain turning force is reached. The reverse drive is needed to be able to remove screws. If you need a really powerful driver, have a look at impact drivers. They are real powerhouses.

The cordless drills are less powerful than the good old corded drill but the difference is smaller nowadays. If you are using a drill a lot or need a very powerful drill, a corded drill is a better choice. But for most hobby users a cordless drill which, can be used both as a drill and as a screwdriver, will be a better choice. This is especially true if you can afford to buy a drill with lithium/ion batteries.

The modern variable-speed drill is a versatile power tool. Most of them have a reversing motor making it possible to use them as a screwdriver as well. With a cordless drill/driver you are no longer limited by the length of the power cord. A keyless chuck makes it easy to change bits quickly. Modern drills have convenient features such as a magnetic bit holder and a built-in LED light.

Despite all the impressive features of the drill/driver you still need to know a little bit about drilling techniques. But first you need the right drill bits. Today you have accessories that can turn your drill into a grinder or sander, just two mention two possibilities. But for drilling, you need a set of standard high speed steel (HSS) twist bits. These can be used both for wood and metal. If you are going to drill in really hard materials such as concrete and masonry materials, you need harder drill bits. But for most tasks around the house, HSS bits will do. You can get good HSS bits at reasonable prices, harder drill bits tend to be much more expensive.

If you are going to drill large holes in wood, you need spade bits. If you are going to use your drill as a screwdriver, you need a magnetic bit holder plus some Pozidriv, Philips and slotted bits.

The two main things to get right are drilling speed and the amount of pressure to exert, known as the feed pressure. As a rule of thumb, the larger the hole and the harder the material, the slower the speed you should use. Another old rule of thumb says, use slow drilling speed when working with hard material and use fast drilling speed when working with soft material. Also remember to lift the drill frequently, to clear the flutes of the drill bit and to increase air flow. It is often a good idea to create a small indentation before drilling to guide the bit’s initial cut and prevent it from spinning out of control.

When drilling through wood, always be careful to prevent the drill from splintering the exit hole. Most people put a piece of scrap wood behind so that any splintering occurs on the scrap wood. If you don’t have any scrap wood, you can slow done just before you break through the wood and stop once the tip of the drill bit emerges on the other side. Now, carefully drill from the backside, guided by the small hole that the tip of the drill bit created.

When drilling in metal, patience is often required. First, make an indentation so the drill bit does not slip. Of course, make sure that the drill bit can handle the metal before you start. Then hold the drill steady and drill slowly. You also need to lift the drill frequently. Just take your time and don’t lose your patience. Note that the metal slivers can be very hot so goggles are very important.

The battery in your cordless drill is very important. A good battery makes life much easier, you get a powerful drill and can work a lot before the battery needs to be charged. Poor batteries on the other hand don’t last long and may still take a long time to charge.

Today, you have three main types of batteries to choose from. They are:

• Nickel Cadmium (NiCd or NiCad)
• Nickel Metal Hydride (NiMH)
• Lithium Ion (Li-Ion)

Nickel Cadmium batteries were the first batteries to be used in cordless drills and they are still used today. They are relatively cheap and can be charged many times, up to 1,000 times. Additionally, they can be charged quickly, although not as quickly as Li-Ion batteries, and Ni-Cad batteries are less sensitive to temperature than NiMH. The latter means that they can be used in both cold and hot environments. But if the battery itself is hot, charging can become a problem. The main drawback is that they are toxic. Cadmium is a heavy metal that needs to be recycled properly. Ni-Cad batteries also have memory effect problems. Note that Ni-Cad batteries are banned in EU.

Nickel Metal Hydride batteries are newer than Ni-Cad batteries. Compared with Ni-Cad they have higher capacity and are less toxic. NiMH batteries have memory effect problems but less so than Ni-Cad batteries. But NiMH batteries can not be recharged as often as Ni-Cad batteries. They also have higher self-discharge rate than Nickel Cadmium batteries. The self-discharge is generally 30% per month or more, compared to 10% for Ni-Cad batteries and between 5-10% for Li-Ion batteries.

Lithium-ion batteries are the newest of the three main battery types. Lithium is light-weight and possesses very good electrochemical characteristics. But it is an unstable metal, for safety reasons pure lithium is not used in batteries. For most purposes, Li-Ion batteries are the best but also the most expensive. They have the highest capacity, are light-weight, no memory effect and low self-discharge rate. The life time of Li-ion batteries is about three to five years, regardless of how much they are utilized. As expected, most high-end tools are using Li-Ion batteries. If you are going to use your drill a lot, paying extra for the powerful but light-weight Li-Ion batteries is well worth considering. The Li-Ion batteries are also considered to be environmentally safe.

Ni-Cad and MiNH batteries suffer from memory effect. It refers to the fact that batteries have lost their maximum capacity after being repeatedly recharged before the battery was flat. For some unknown reason, the batteries seem to remember the smaller capacity and forgotten the original capacity. Note that Li-Ion batteries have no memory effect. Also note that memory effect has nothing to do with the age of the battery. All rechargeable batteries will lose storing capacity over time, due to secondary chemical reactions within the battery.

Batteries have an Amp Hour (AmH) rating.  It indicates how much energy can be stored in the battery, thus measuring the capacity of the battery. It is the current flow, in Ampere, multiplied by the time of discharge, in hours. If a battery is rated at 20 AmpH, it can sustain a 1 Ampere draw for 20 hours. Just bear in mind that the listed AmH for different batteries may not have been measured in the same way, so higher AmH does not guarantee that the battery is better.

Fast battery chargers are very handy, not just for professionals. If you are using power tools for longer periods, a rapid battery charger makes it possible to work all day with just two batteries. The modern rapid charger charge batteries in 30 minutes or less. But several companies are working on much faster charging times, just a few seconds may be enough for charging batteries in the future.

It was not a long ago when rechargeable batteries were almost useless. Even you charged them according to the recommendations, it generally did not take long before they lost most of their power. Charging the batteries required a lot of time and as mentioned, the batteries generally had to be replaced fairly soon. But with the success of cordless devices, battery technology has improved a lot lately. Even better, prices have fallen as well.

Lithium-ion batteries are powerful and have very few shortcomings compared with earlier rechargeable battery types. And with the rapid 30-minute fast chargers, you generally only need two batteries to keep you covered. Additionally, lithium-ion batteries can be charges thousands of times without losing much of their initial capacity.

But not everyone is happy. Especially smartphones with their large displays are draining their batteries quickly. And while it is not really inconvenient to change the batteries of a cordless drill, you don’t want to keep on changing or charging the batteries of your smartphone all the time. So a solution is needed.

One very interesting potential solution is superfast chargers, charging the batteries a hundred times faster than current chargers. It is actually not the charger that is important, the batteries need to have the right internal structure. In theory, it is possible to charge lithium-ion batteries in a minute or two. It is actually relatively easy to construct such a solution on paper. The real problem is to find a way of producing such batteries in a cheap and reliable way.

A number of projects are trying to find a solution that can be commercialized. The market is huge, power tools would be a relatively small market compared with smartphones and laptops.

How fast a battery can be charge is primarily limited by the movement of electrons into the cathode. But one of the main problems is that fast charge times generally mean less capacity. If you decrease the charge time, you also end up with a weak battery. If you want a powerful battery, the charge time increases. As mentioned, there are solutions to this but the real problem is to find a way of producing reliable batteries in large quantities, to reasonable prices.

Cordless drills have become very popular, nowadays they are cheap and powerful. The early cordless drills were not very powerful and the battery did not last very long. Things have changed a lot since the early days, nowadays cordless drills are generally superior to mains powered drills. But for some people, a cordless drill may not be the right solution. Here is an overview of the cordless drill vs. corded drill topic.

An electric drill is the most useful power tool, every now and when you need one. The good old corded drill is cheap but nowadays a cordless drill can be a better choice. For many professionals, cordless drills are the best choice. A cordless drills is not limited by the cord and is suitable for most tasks. By having two batteries, the drill can be used non-stop. Once the battery is flat, replace it and charge it in a fast charger. It will be charged before the other battery is flat. Thanks to the fast chargers, batteries can be charged in less than 30 minutes.

But if you are only using your drill once in a while, then you may find that the battery is flat even if you haven’t used the drill. Self-discharge is still a problem. Most batteries have a self-discharge of about 10% per month. Also, batteries don’t have unlimited lifespan. With a corded drill, you don’t have such problems.

A good cordless drill can be used as a hammer drill as well as a screwdriver. If you buy a drill with hammering action, you can drill holes in concrete. Hammer drills have a switch that enables the hammering action, so they can be used as standard drills. The hammering action will damage softer materials. If you are going to use your drill has a screwdriver, it should have a reversing switch which changes the direction of the rotation. This makes it possible to drive and remove screws. The drill also needs to support slow speeds and preferably have an adjustable slip-clutch mechanism. This prevents the drill from damaging the screw or the workpiece.

Despite that cordless drills have a battery, they typically weight a little bit less than corded drills. But cordless drills are more expensive. So if you are seldom using a drill, a cheap mains powered model may be the best choice for you. Note that if you need a drill with hammering action, i.e. a hammer drill, you may prefer corded hammer drill. The hammering action drains the battery quickly. But apart from the problem with the energy-consuming hammering action, a cordless drills is a very versatile tool and nowadays relatively cheap. In most cases, a Ni-Cad drill is the best budget solution while a lithium-ion drill is the best choice if you need a powerful cordless drill. Ni-Cad batteries are heavier, bulkier and less powerful than the more expensive lithium-ion batteries.

Hammer drills are very versatile tools, not just for professionals. The basic hammer drill has a switch which disables the hammering action, turning it into a normal drill. Many hammer drills can also be used as screwdrivers as well. You also have much more powerful hammer drills, the rotary hammer. It is the right tool for drilling in really hard materials, such as concrete. Here is a short hammer drill overview.

For most DIY tasks the standard hammer drill is the best choice. The hammering action makes it possible to drill in hard materials. And you can disable the hammering action when you don’t need it. The hammering action generally damages softer materials. So if you are going to drill a hole in a concrete wall which is covered by a layer of plaster, you need to be careful. The hammering action will damage the plaster. The solution is to drill without the hammering action until you reach the concrete behind the plaster, then you enable the hammering action.

In most cases, a cordless drill is more convenient than a corded drill. But if you are going to use the hammering action a lot, you may prefer a corded hammer drill. The hammering action quickly drains the battery.

Of course, you also need drill bits that are meant for masonry drilling. Standard drill bits will quickly break if you use them in hard materials. But note that the rotary hammer uses its own special bits.

If you are going to do a lot of drilling in hard materials, you may prefer to use the more powerful rotary hammer rather than a normal hammer drill. It has a piston mechanism that does the hammering action. This makes the hammering action of the rotary hammer much more powerful, letting you drill holes much faster. But you can’t use drill bits meant for hammer drill. The powerful action of a rotary hammer requires special bits that lock tighter into the hammer. Ordinary bits are too smooth, they will be pounded loose very quickly.

Rotary hammers are too big and clumsy to be used in soft materials. But you can disable the rotary action and turn the rotary hammer into small destruction hammer, which can be used for chipping jobs.

The combination hammer is a combination of rotary hammer and demolition hammer. You can use them both for drilling concrete as well as for chiseling and chipping. Of course, they are not as powerful as standard demolition hammers but you get good value for your money. Demolition hammers are similar to rotary hammers but they lack the rotary action needed for drilling. It is the tool for demolishing concrete and masonry.

Note that hammer drills often have three modes, rotary, hammer and rotary+hammer. Rotary mode means standard drilling, without the hammering action. Hammer mode means that the drill does not turn, it just hammers, this is useful for chipping. The rotary+hammer mode is used when drilling in hard materials. The basic models seldom have the hammer only mode.