Drill bit cutting speed
Drill bit cutting speeds are very important in the drilling of metals. Drill speed becomes increasingly important when drilling harder metals. We have produced speed and feed charts for both metric and imperial drill bit sizes. You should use these feed and speed charts as a guide as there are many variables involved when drilling metal.
What drill bit cutting speed for drilling metal?
Factors which will influence drilling speed and feed, and therefore you must considered, when drilling metal include:
- The metal being drilled. You should Identifying the metal being drilled, this will allow you to determine the hardness of the metal and how the metal reacts to drilling.
- The hardness of the metal being drilled. The harder the metal the slower the drill speed required.
- Use of cutting fluid. You should always use a cutting compound or cutting paste when drilling metal. The use of cutting fluid will make the cutting process easier and will therefore allow for a faster cutting speed.
- Type of drill bit being used. There are many different types of drill bits available for drilling metal and each type will have different speed ratings.
- The diameter of the hole being drilled. The larger the diameter of the hole you are drilling the larger the surface area where metal is in contact with metal as a result heat build up will be faster. The larger the diameter of the hole the slower the feed rate.
- The depth of the hole being drilled. If the depth of the hole you are drilling is more than twice its diameter it is advisable to reduce the drill bit speed as heat will build up will be accelerated.
- The use of a pedestal drill or hand drill. If you use a pedestal drill you will more accurately position your drill bit. Therefore feed rates and speeds can be accurately adjusted.
Drilling Feed rate
Feed rate is the speed at which the drill bit travels through the item it is is drilling. For anyone drilling by hand this measurement will mean very little and would be impossible to maintain accurately. Experts agree that you should use enough pressure to maintain a continuous cutting action. Ideally you should create a constant stream of cut metal for removal from the drilling hole.
You should avoid exerting too much pressure or you will cause excessive heat build up which will hamper the cutting action. Moreover if you use excessive pressure you will also increase the likelihood of the drill bit breaking.
Drilling cutting speed and feed charts are often produced as guidelines for drilling in manufacturing where speed is important.
Where drilling cutting speed is not the primary focus it is advisable that you use a slower speed than recommended as this will help you prolong the life of your drill bit.