CNC machines are an essential part of the hacker’s toolset. These computer-controlled cutters of wood, metal and other materials can translate a design into a prototype in short order, making the process of iterating a project much easier. However, the software to create these designs can be expensive, so [Franklin Wei] decided to write his own. In particular, he decided to write his own program to engrave images, converting a photo into a toolpath that can be cut. The result is RasterCarve, a web app that converts an image into a GCode that can be fed into a CNC machine.

The motivation for this project was to learn how to do it, but also frustration at the cost of software such as PhotoVCarve. Costing $149, this program does much the same as the one written by [Wei], albeit with a number of additional bells and whistles. He does an excellent job of describing how the conversion process works: his code creates a series of paths across the image, then converts the color of each pixel into a depth: The darker the image, the deeper the cut.

He also describes the process of taking this simple code and converting it into a Javascript web app, a process that has driven many a programmer to madness. It just goes to show that, although using other people’s stuff is fine, it often makes sense to try and do it yourself.