Drilling Basics

A modern drill is a very versatile tool. A drill with a reversible motor and variable speed can be used as a screwdriver. A hammer drill has an additional hammering action which is handy when drilling in hard materials. Thanks to lower prices and improved batteries, cordless drills have become very popular. Many drills have handy features such as keyless chuck, making it quick and easy to change bits, and built-in LED light which is convenient when working in dark places.

But even if you are using a good drill, you need to know a little bit about how to drill. Power tools are very good but they can also do a lot of damage if wrongly used. But first you need to use the right drill bit. A set of good drill bits is important for good results. Fortunately, for most materials inexpensive drill bits will be good enough.

For DIY drilling around the house, standard twist bits made of high speed steel (HSS) will be the best solution. HSS bits are cheap and can be used for both wood and metal drilling. If you are going to drill through steel, HSS bits with titanium oxide coating, often called titanium bits, are the best solution. Note that while normal HSS bits can be sharpened HSS bits with titanium coating can’t. Concrete and bricks require special masonry bits.

Good drilling technique is pretty much made up of just two things, the right speed and the right feed pressure (how much pressure one should apply). As a rule of thumb, use slow speed when drilling large holes or through hard materials. High speed should be used when drilling small holes or through soft materials.

To make sure that the hole is made in the right place, make a small indent before starting to drill. This also prevents the drill bit sliding away from the drill location. Remember also to lift the drill regularly, this clears the flutes of the bit which improves air flow and prevents the bit from getting too hot.

Drilling in wood is generally straight forward but you must be careful so that the bit does not splinter the wood when exiting the wood on the other side. The easiest way to avoid this problem is to put a piece of scrap wood behind so if splintering occurs it will be the scrap wood which is damaged.

Drilling in metal requires patience. It is not difficult but it will take time, you should drill steadily and slowly. Also beware of flying debris, hot slivers of metal can cause damage if you are not careful.

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