A CNC routing machine is in very basic terms a router which is controlled by computer. For some, CNC machining may seem complicated and very technical. This article hopes to demystify CNC cutting and will show the basic theory behind CNC machining.
Our CNC routing machine makes use of a normal router motor. As some of you will know, a router is the tool of choice when it comes to profiling the edges of your work pieces. It’s also useful when you want to create a decorative wooden sign or carve some writing into a workpiece. To do this the router master would create a stencil of the artwork, place it onto the work piece and start routing. The router is indeed an excellent tool and accomplishes this task quite easily.
But what if you wanted to make a lot of wooden signs, or if you wanted to profile a lot of edges. Doing this by hand would not only take a long time but it would also sap a lot of the router masters energy. A CNC machine will be able to acomplish this mass production task without much effort on the part on the router master. For instance if you wanted to create 100 wooden signs, all you would need to do is create the design of your sign on a computer program and then let the machine do the rest. One program – multiple cuts.
I think it would be a good idea for me to explain how our CNC machine works. Going back to when you were in primary school, you’ll probably remember those X-Y planes where we had to draw geometric shapes. To find a co-ordinate like X – 5, Y – 5, you would start in the bottom left of the plane and move to the appropriate position using the co-ordinates. Next you mark the spot and presto thats where the co-ordinate is.
A CNC machine works in a very similar way. Turn the router attached to the CNC on and then tell it to go to from X – 5, Y – 5 to X – 10, Y – 5. If you’re using a V-bit and it is 2mm into the material it will cut a straight line, and if we’re working in millimeters the line will be 5mm long.
Remember that a CNC machine not only works with an X-Y plane, you’ve also got a Z-axis.This means that a CNC machine can not only go to different X-Y co-ordinates on a flat plane, but with the Z-axis it can also go up and down. This adds depth to your work and gives you the ability to create 3D components – a really nice addition to any woodworking project.
The real genius of a CNC machine is in the computer software. You would create a design in the software program like the one on the right.
The software program will automatically convert all the lines in your design into X-Y-Z co-ordinates.
Now all you do is pass these co-ordinates to your CNC machine and it will make the necessary cuts as it moves through the material.
The software allows you to simulate what your piece will look like once it has been machined.
The other great thing about CNC machining is that you can create very intricate pieces of work. For instance the machine which we have can accurately cut to 0.05mm. And I’m sure there are machines which have even more accuracy.
CNC machining has advanced our capacity to produce high quality, accurately made products at high speed. The very table where your computer sits may have been cut using a CNC machine as well as many other components found all around us.
This article brought to you by Wooden Works: