3D printers are a fabulous introduction to CNC machining, with their small desktop profile and practical applications for prototyping work. While generally simple to use, several steps are still involved to get from design idea to 3D product. Typically students will have to spend some time learning at least a rudimentary CAD program in order to put their ideas into something workable. This could be as simple and cheap as TinkerCAD or as complex and expensive as Solidworks, for example. Next the CAD file is converted to .STL format and imported into the CAM program such as Slic3r or ReplicatorG which converts the CAD file into gcode, mapping out the tool path of the extruder as it lays down the plastic in thin spaghetti-like strings. All of this is easier than it seems but it does have a steep learning curve. One of the fundamental advantages of a desktop 3D printer (or small CNC mill for that matter) is the fact that design files can be shared across the planet and manufacturing in a short time locally. The unique prospect offered by OmNomNom (available for Mac OS 10.7 and above only) is that virtually any 2D image can be instantly converted to a 3D printable .STL file. Its just a drag and drop affair, where you locate a 2D image that you want to create in 3D, and drop it into the program and it is ready to print. This represents a huge simplification in the skills necessary to use a 3D printer, eliminating the design phase entirely and allowing the user to find what they want and well, just make it. Bear in mind that simplification means limitations too, and students can use this to get their printing skills off the ground but advanced designs of their own are still going to need the more traditional approach to desktop CNC. Take a look and if you have the right Mac hardware and software, OmNomNom may just be a gateway to 3D printing for your STEM students in the fall.
CNC Machine A Robot Roving Eye Part II
CNC Machining an Arduino-Powered Robot Roving Eye.