Drilling and milling are both machining processes with lots of similarities, it’s more critical to figure out their difference when you want to select one of them for your project. Follow us to distinguish milling and drilling, also find out the difference between milling machine and drill press.
CNC milling and drilling are two widely used subtractive machining processes that creating the desired part through removing materials. Then how to distinguish between drilling and milling, what are the exact difference between them?
1.Capabilities. Drilling or CNC drilling is a machining process used to produce a through or blind hole in a workpiece. Milling operations can be utilized to create flat, contoured, and helical surfaces, for thread and gear cutting, and more purposes.
2. Speed. The permissible cutting speeds and feeds for milling are three to four times higher than those for drilling.
3. Surface quality. Generally, the quality of the surfaces machined by milling is superior to that of drilling.
4. Cutting tool. A milling cutter usually refers to a multi-edge cutting tool with the shape of a solid of revolution, and the cutting teeth arranged either on the periphery or on an end face or on both. Common milling cutters including plain milling cutter, face milling cutter, side milling cutter, angle milling cutter, T-slot cutter, end mill, and form milling cutter. The drill is a cylindrical rotary-end cutting tool, it can have either one or more cutting edges and corresponding flutes, which can be straight or helical. Common drills including twist drill, core drills, gun drills, and spade drills.
5. Machine. The drilling operation can be carried out by using either hand drills or drilling machines, milling is only done with a milling machine.
6. Working principle. Drilling involves producing holes by forcing a tool that rotates around its axis against the workpiece, the stock remains stationary on the table. In the milling process, material removal is achieved by combining the rotary motion of the milling cutter and linear motions of the part simultaneously.
7. Feed. For drilling, the feed direction is always axial to the cutter, the feed can be achieved either by moving tool or workpiece, while in milling, the feed can be given at any angle to the axis of cutter, and the feed motion is usually completed by moving the workpiece.
8. Contact with workpiece. In drilling, all cutting edges of the drill bit continuously contact with the part to be machined, in milling, the cutting edge simultaneously engages and disengages with the workpiece. Each cutting edge cuts material from the workpiece only for a period of time during each tool rotation. This also leads to a difference in the length of chips.
1. Capability and versatility. Milling machines are usually used to cut flat surfaces, they are also capable to create irregular surfaces and slots, as well as perform drilling, reaming, and other operations. The drill press is primarily applied to cut round holes in solid materials. A mill can work as a drill press and provide more capabilities.
2. Axis of motion. The drill press only involves one axis of motion and can move either up or down along a straight line, it is suitable for vertical plunging but can’t cut in the side direction, the milling machine allows the worktable to move in the X, Y, and Z directions.
3. Size and weight. Drill presses are generally smaller in size and proportions than mills. Drill presses are usually lighter and often placed on top of the workbench and operated by hand, while milling machines usually directly set up on the floor and take much more space.
4. Accuracy. The milling equipment can move in all three axes simultaneously and the finished product has higher accuracy than that produced by the drill press.
5. Rotational speed. High RPM may cause problems in chip evacuation and breakage of drill bit, so low rotational speed is often used on a drill press. Milling machines can apply a high rotational speed.