A CNC router machine is probably the most useful tool a hobbyist can own, but the price for a CNC machine on the market is way more than the average hobbyist is willing to spend. You can build your own CNC with very basic tools, little knowledge of machinery, mechanics, or electronics, but be warned, these machines are inherently dangerous, so wear the proper protection and use common sense. At the very least, read the instructions and precautions on every tool you use.
Now, a CNC stands for Computer Numerical Control, but that is gibberish. It does hint you to the fact that something is controlled, and probably by a computer. It's really a mechanism that interfaces to a computer to control its movements, similar to a robot, but this machine has a specific function. It cuts or shapes things with this control. In essence, a computer precisely controls a cutting tool, like a router for instance, to cut materials such as wood, plastic or metals into shapes only bounded by your imagination.
This video tutorial will show you how to make the y-axis motor mount for a CNC router. For the structure of the machine, you only have the three motor mounts remaining. We have recently completed the last two screw assemblies (x and y). The machine now is stiff as an MDF board and won't move anymore. It was more fun without the screws, wasn't it. Now we need to add a method of spining power to these screws. We can't just use our fingers to turn the screws, but we could attach steering wheels if you're looking for a manual routing machine. We won't be able to call it a CNC anymore, however.
These mounts are real stupid simple. All we're going to do is take a piece of MDF and put about 7 holes in it, varying sizes of course.