Understanding The Different Kinds Of Drill Bits For Metal
There are many different kinds of drill bits for metal, and depending on the application, there are numerous ways these drill bits are used to meet the specific drilling requirements. In milling and fixed metal shaping, it is common to see solid carbide drill bits in use. They work well in high temperature and abrasive situations. But because of their metal composition it is possible to break these drill bits if you are no careful. The bits need to be set in a ridged and stable spindle system, making these drill bits for metal hard to use.
Cobalt drill bits are used for drilling and boring extremely hard metals, such as treated stainless steel and heated treated metals. Along with other sheet metal tools these drill bits work wonders in the aviation sector. They stand up well to the most abrasive drilling situations, but are very expensive and require skilled handling. In most common drilling situations where large holes or countersinking is required, the piece that is drilled is usually secured in a vise or jig. Which in turn is clamped on a work bench, and then drilled in steps to make sure that the hole is straight and the work piece is not damaged while being drilled.
Choosing the right drill bits for metal fabrication is very important, especially when the work piece is large, or requires a precise drilling angel. For most large drilling applications, an end mill or vertical lathe is usually used for full control while drilling. Sometimes in high heat situations a drilling lubricant is used to prevent premature drill bit failure or breakage, and to ensure that the part being drilled is not damaged or cracked. Some metals such as bronze and other non ferrous metals can become discolored from the heat of drilling, making it necessary for constant lubrication. Some metal cutting tools even come with an automatic lubrication system to ensure the metal doesn't discolor.
Because some drill bits for metal are very expensive, they are resharpened by machinists to provide the longest life possible. In addition to sharpening the machinist will also make sure that the proper contact angle is set so the drill bit bites into the metal at the right position for optimum drilling. When boring large holes, whether in length or diameter it is sometimes necessary to temporarily weld or fasten the part for drilling into a work jig. This will reduce the chances of slipping or creating vibrations that could hinder the drilling when precise drilling or shaping is called for.
Choosing the rights drill bits for metal working and fabrication is just as important as the design of the part itself, poor or off center drill holes could actually ruin an expensive part or cause fit issues later in production.
