Making a CNC. Part 1

Hi Steemians, I have started a personal project to make a CNC machine, which is a numerical control machine and works in a similar way to the 3D printer, it read a file in gCode format and it mechanizes a 3D piece or model from a block of material; it is similar that a sculptor would do when carving a figure from a compact stone

The difference between a manual machine and those of numerical control machines is that in CNC machine the computer controls the movements of the motors both position and speed that drive the axes of the machine. Because of this, you can achieve movements such as circles, diagonal lines or other different 3D figures that would be impossible manually. CNC machines can execute movements of their tool on the X, Y, and Z axes at the same time

In the industry there are different types of CNC machines, some of this work with steel and heavy metals, others cut sheet metal with plasma and others work with aluminum, plastic and wood.

The design that I will present below will be detailed step by step, I have taken some references from the web to which I have added certain updates and improvements by simplifying 3D printed parts with plastic PLA, the final goal of this machine is that is dual either for cutting acrylic sheets with a router or cutting metal sheets with plasma. The project is broad and I want to detail all the construction and the step by step of the manufacture of the machine in a series of publications

The first phase of the project includes the design of the head which has to be strong and resistant enough to support a cutting router, besides the materials to be used are not so expensive and available in Venezuela. The CAD model was digitized using Autodesk Inventor and then cut and welded into 3 mm thick sheets to create a robust and functional piece.

Regarding the displacement system, one of the most economical options contemplated was the creation of two (2) lateral pieces in which 608 bearings are used, which are the most common to achieve the displacement of the trolley in the lateral beam, an alternative to the system of chromed bar of 12 mm of diameter that in addition to being expensive are not obtained; As an alternative to the trapezoidal screws we will use belts type T2.5 whose detail will be illustrated in the following post, for the head original designs were created in 3d printing, blocks of 48 mm, to insert the linear bearings lm8uu, and a guide bearing for the trapezoidal bar. All this last will be shown in my next publication.