What is this DIY 3D printer?

What is this  DIY 3D printer?  I would say it a hobby that build 3D printer for fun,  most of the time is because the builder wanted to create part for his other project, like me, I wanted to to build part for my own coaxial copter design.  Anyway I make a lot of mistake in my choices on how to build the 3D printer.  I hope by sharing my experience, you can avoid the mistakes.

To understand 3D printer, you really need to understand the key component of the printer:

• Printer frame that hold the stepper motor and print head, you could say it a 3 dimensional plotter. It need to support X, Y and Z direction movement.  Stable frame will improve your print quality.  The frame design normally is the printer design name, by selecting the printer design name, you basically selecting the printer frame.  Reprap printer tree will help you to understand the design history of the frame.

• Arduino base controller board, it normally have AVR micro-controller, recently we are seeing ARM base controller too, it the brain of the printer that controller all the stepper motor and print head.

• Firmware that run on the controller board,  normally a GCODE interpreter, GCODE is most commonly used programming language in CNC domain, it have command such as drawing a circle, goto location and some control such as turn on the heating element.

• Printer head is normally a plastic extruder, it design to extruder plastic in a control way,  it consist of a motor and gear that push the filament in to the hotend, hotend have heating element and temperature sensor use by the software to maintain constant temperature so that you get consistence plastic output from the print head.

• Print bed is the area where 3D object to be printed, it also provide another very importance function: to hold down the part to be printer. if the part move during print, you print is basically ruin. Holding down printing object is another major issues in 3D printing.  There is a lot of way to secure the object down, like heated bed and Kapton tape.  It an area that need a lot of fine tuning.

• Stepper motor is the mechanical part that provide the motion, normally you need to select the suitable size, and the stepper motor controller or driver will determine you print resolution, how fine you can print is control by the step.

• Power supply, depend on the material you plan to print,  you will have difference requirement.  Normally if you plan to print ABS or nylon, you need power supply that can handle over 150W.  

• PC, you need this to send the GCODE to the printer as well as doing the initial calibration.  with the recent advancement, we are seeing web base controller that allow you to do all the calibration in the printer itself, but still you need to have a host to create the GCODE file.

• Slicer program, it a program that convert 3D object to GCODE that controller use to create/draw the part in 3 dimension.  Most common support input format is STL.  The most popular 3D slicer is Slic3r.

• 3D model, you can create them in one of the CAD program or download from site such Thingiverse.

• Printer calibration, although it not a component of the 3D printer, but it the most critical part of the process.  How well you print come out depend on how well you calibrate your printer.  

Will continue tomorrow to talk about each component in detail.