Test CNC Machine (GROUP PROJECT)

What's CNC?

The numerical control by computer, or better known as CNC, is a system that allows to control at all times the position of a physical element, usually a tool that is mounted on a machine. This means that by means of a software and a set of orders, we will control the position coordinates of a point (the tool) with respect to an origin (0,0,0 of machine).

The CNC controls all the movements of the tool when we are manufacturing and not only the coordinates, but also the way to move between them its speed and some more parameters.

How does the routing work?

Routing is a roughing process.To this end, a cutter with cutting edges is used, which cuts the material by means of chip cutting when turning.

The CNC Router works with the two axes, X and Y, this allows the cutting tool to move and rough out in both dimensions.

The Fablab Yachay has a CNC SHOPBOT Alpha milling machine of dimensions 2440 x 1220 mm. To test the CNC machine, in group work, we manufacture a device that allows to validate the pressure adjustment.

Before starting the practice of the week some important elements of the CNC machine are recognized.

Before of manipulate the CNC machine is very important following safety tips:

When you are working with a CNC machine of any size, always use personal protective equipment to reduce the likelihood of an injury. CNC machines are controlled by computers that must be programmed by the operator.

All CNC machines have an emergency shutdown switch that is usually located on the control panel, and can stop the drilling in case of malfunction of the machine. Locate this switch (some machines have more than one) before operating it.

The machine will do what it is told, even if it is a dangerous command; therefore, the programmer must be careful when designing and programming it.

Before turning on the machine, make sure that the materials are centered on the center screw bench and that the tip of the correct router is set

When the piece is finished, turn off the CNC machine, before removing the work.

Manufacturing test device (Group Project)

For instruction in computer-controlled machining in group assignment we have designed a device that allows us to validate the press fit, this device allowed us to find the ideal measure to subsequently apply the parameters and exact measurements in the final design of the assignment this week.

The main consideration when cutting on a CNC router is the shape of your cutting tool. It is not possible to make square inside corners using a round end mill. You can approximate squareness by decreasing the tool diameter, but there will always be a little extra material in the corners obstructing material passing through.

The easiest way to circumvent this limitation is to remove extra material from inside corners. These extra cuts are commonly called "dog bones" due to the shape of the resulting hole or notch

Import design to V-Carve Software

VCarve Pro provides a powerful solution for cutting parts on a ShopBot CNC Router. There are tools for 2D design and calculation of 2D and 2.5D toolpaths and along with the ability to import and toolpath a single 3D model (STL, OBJ etc.). There is also support to import multiple Vectric Clip Art 3D models (V3M) to create 3D assemblies.

Setting parameters in the machine

Start cut

Make something big (on a CNC machine)

For this assignment I made a piece of furniture for the desktop in the solidworks software, then the steps of design and fabrication by CNC cutting are indicated