Printing In Three Dimensions

1. Printing In Three Dimensions

2. The true benefits of 3-D printing lies in the technology’s ability to provide RAPID PROTOTYPING Being able to make prototypes prior to developing and machining the injection molds used in manufacturing can identify errors and design flaws in geometry and dimensions before the final product is put into production. This ability saves time, money, and resources. Three dimensional printing allows a manufacturer to go from an engineering drawing to a design faithful object in minutes or hours instead of weeks or months as was the case with traditional prototyping methods.

3. 3-D printing is an additive process. This means the build table starts off empty and material is added until a finished object is created. CNC or Computer Numeric Control is a subtractive process. This means that a block of material is placed on the build table and it is specifically carved, shaved or machined until it takes on shape the of a finished object.

4. REPRAP The term RepRap was coined to refer to Rapid Replication, or Rapid Replicator. While 3-D printing allows the relatively rapid replication of a virtual image it is too slow a process to be a primary method of mass production. The strength in the 3D printing process is that it can be used to make a positive from which an injection mold can be made. The injection molding process is a fast, mass production process.

5. Extrusion Type 3D Printers are Industrial Robots ! It’s actually a Cartesian robot that moves up-down, in-out and right to left. That’s three degrees of freedom. The end-effector is the hot end or extruder that pushes out a stream of melted plastic. It is an additive process It is currently too slow to be a primary mass production process, however advancements may speed it up to the point that it might become a primary mass production process !

6. CNC Machines are Industrial Robots ! It’s actually a Cartesian robot that moves up-down, in-out and right to left. That’s three degrees of freedom. The end-effector is a rotating cutting tool that cuts away material from a block. This is a subtractive process ! It’s faster than 3-D printing and is currently used directly as a mass production process

7. 3-D Printer Whether it is CNC or 3-D printing, both systems are driven by computers. Carvewright CNC Some machines are connected directly to the computer while others receive computerized instructions from a memory module that is first connected to a computer then it is removed then plugged into the machine.

8. G Code Addititve – Subtractive CNC – 3-D Printing No matter how the files are developed, drawn or digitized from a photo, they must be converted to g code in order to direct the movement of the end-effector in either system.

9. G Code is a computer language that people use to tell a computerized machine what to do and how to do it. It is an early code developed in the 1950’s at MIT. Over the years it has morphed into many forms and variations.

10. Normally, we don’t program or write in g code!! More commonly, an object is drawn on a CAD program then rendered as a 3-D illustration or created by a solid modeling scripting program. This object was drawn then saved as a .stl file. It is then opened by a slice program, “sliced” and saved as a g code file. It can then be loaded into the printer interface or CNC controller software for printing or machining.