Sunday, May 24, 2015
CNC is a big thing. You might think of it as the 2d version of a 3d machine. With a 2d machine you remove material and with a 3d machine you add material to get an object. Always have wanted to build one myself. Have the stepper motors, just have to make the rack.
Numerical control (NC) is the automation of machine tools that are operated by precisely programmed commands encoded on a storage medium, as opposed to controlled manually via hand wheels or levers, or mechanically automated via cams alone. Most NC today is computer (or computerized) numerical control (CNC) in which computers play an integral part of the control.
Nowadays you can get a computer and almost do all of it yourself. First you have to have a drawing prepared. There are lots of existing artwork you can use or you can create your own .svg files with Inkscape. Scalable Vector Graphics (SVG) is an XML-based vector image format for two-dimensional graphics with support for interactivity and animation. The SVG specification is an open standard developed by the World Wide Web Consortium (W3C) since 1999. SVG images and their behaviors are defined in XML text files. See also https://www.google.com/?gws_rd=ssl#q=inkscape+tutorial
Once you have created your graphic or use and existing one, you can use a specialized version of linux know as linuxcnc.
You can also use a program called Jscut that can run from a web server or a local machine. The advantage is that you can install it once and use it many times where ever you are at. Most systems generate gcode.
G-code (also RS-274), which has many variants, is the common name for the most widely used numerical control (NC) programming language. It is used mainly in computer-aided manufacturing for controlling automated machine tools. G-code is sometimes called G programming language.
In fundamental terms, G-code is a language in which people tell computerized machine tools how to make something. The how is defined by instructions on where to move, how fast to move, and through what path to move. The most common situation is that, within a machine tool, a cutting tool is moved according to these instructions through a toolpath, cutting away excess material to leave only the finished workpiece. The same concept also extends to noncutting tools such as forming or burnishing tools, photoplotting, additive methods such as 3D printing, and measuring instruments.
Jscut is certainly easier than generating Gcode by hand then feeding a papertape into a nc machine. You do need to know what cnc is about to really use the Jscut. See also: https://www.youtube.com/watch?v=dVgf0Hf91vA
What will you make?