A Milling machine for everything
The milling machine is one of the most important workshop tools in our days. It gives you the freedom to create most parts for use in the workshop. This leads to a more efficient workflow, less dependency from manufacturers, reduces the time to complete a work and you will even get some of your parts cheaper. A milling machine is an indispensable part of the manufacturing industry used from giving shape to a material, to producing mouldings, print outs, electronic boards for assembly, woodwork, stone work, metal, lathe, etc, the applications are endless.
Milling machines are easy to use either manually or computer controlled. By securing a piece in the milling machine bench you can move the piece in several axis. This allows you to drill with precision whatever shape you require. In the case of the computer controlled machines a material can be shaped into almost anything in a very small amount of time.
A milling machine is easy to maintain, the consumable parts are cheap and easy to get the only downside is the leftovers of the material being shaped. Usually the larger machines are self contained with vacuum systems to remove this left over bits and require regular cleaning and lubrication. The smaller machines are easier to clean and lubricate but usually they do not contain the residues with the machine, this is partly resolved by placing a vacuum hose next to the drilling tip.
What’s a milling machine
There are different kinds of milling machines for different jobs and sizes. They can go from desktop to industrial “monuments” according to the needs. Machining setup requires the work piece, the tool and the machine. When using the machine the work piece moves relative to the tool while the tool removes the excess parts of the piece according to the blueprint or technical drawings.
A milling machine has two main parts:
The head that holds the tools used to mill the materials, which moves up and down on the Z axis together with a motor that spun the tools. The motor is can be of variable speed or you can control the speed by a gear system attached to the motor.
The table moves across the X-Y plane by turning hand-wheels which will position the material under the head or move it against the cutting tool.
The cutting tools to use with your milling machines
You can use different tools for different types of cutting and also depending of the material used. The drill is the most common piece. It’s placed in the collect and lowered into the material while spinning to drill a home in the material being milled. The mill is used to cut material though and around the material until you achieve the desired outcome. A tap is a piece similar to a drill used to cut threads for screws to fit into it, just like a nut, this way you can screw another part to the hole that you used the tap in it.
CNC milling machines – What is it?
A computer controlled milling machine or CNC milling machine makes precision parts with almost no intervention from the operator. By using special motors called step motors we can achieve precise measuring and thus precise parts that are too difficult to do manually. The operator still needs to be trained to ensure that the machine operates accordingly, to check if the parts are according to spec, replace any consumable tool and set up the machine to the required settings for each part. The machine needs to be programmed with the drilling positions and the right axis movements to produce the part. The operator needs to do this manually at a computer terminal, at the machine itself (professional machines comes with a computer inbuilt) or more commonly used and less time consuming is the use of computer–aided manufacturing software (CAM)with computer-aided design software (CAD). Although it seems complicated it is far from it, due to constant improvements in the software you can get programs that will calculate all the required data to program the CNC just from a 3D drawing. These 3D drawings can be ordered online, bought from a list of providers, designed in a 3D software like AutoCAD, 3D Studio Max, Maya, Rhino, Google Sketch(free), etc, and in case you cannot find your object online you can always take several pictures of the different sides and easily get it done in one of these 3D programs.
The most common types of milling machines
Milling machines are so versatile that a single machine can make a multitude of objects or products. But some objects require a different type of milling machine. This is so due to difficult angles that the desired part requires to be produced that a normal milling machine cannot reach. Other reasons to use a different type of mill is the space of the workshop, the type of material to be used, the size of the object, the shape of the object and efficiency factors.
The vertical milling machine has the cutting tool positioned vertically over the table. This way the cutting tool is pointing downwards into the material surface we want to model. Moving the cutting tool up and down and the table in the X-Y plane allows us to cut, drill or carve away different sections of the required object. This is the most common type of milling machines used.
The horizontal milling machine has the cutting tool positioned at a 90 degree angle from the machine. The tool moves up-down while the table moves from side to side allowing the object to be shaped in different positions.
The combination milling machine combines both the horizontal and vertical tool settings and it can use both of them at the same time to make simultaneous cuts. One other variation is a milling machine with a table that moves forward and backward and side to side together with a cutting arm that moves up and down and side to side. This will allow the machine to perform more accurate cuts and reach even more difficult angles.
The Bridgeport milling machine has wider range of motion spindle and it can be set into a variety of positions. This makes a more flexible machine and allows for the creation of more products like parts and even plaques.
One of the simplest types of milling machine is the column mill. It’s a vertical milling machine with a long pillar that suspends the cutting tool over the cutting surface. It is used to drill bores into metal and shaping small metal tool. It is very popular among hobby millers in the car and metal industry due to its small size and price.