Putting an end to months of wondering how 3D printers work, we ordered a FLSUN Kossel Delta 3d Printer for US$250
Assembly took us 8 hours split over 2 evenings, because of our innate inability to follow instructions
Understanding the printer:
A triangular prism made up of aluminum bars and held together by plastic joints forms the printer frame
Except for the aluminum bars, everything else can be fabricated using the 3d printer
3 carbon fibre rods connect the extruder to tension belts along the frame
Each belt is controlled by stepper motors hidden in the printer base
Differential movement of each motor determines the position, speed and direction of the extruder head
A MEGA 2560 chip (also hidden in the base) powers the printer
Software wise, we opted to use Slic3r and Repetier Host
Slic3r turns 3D models into a long list of x,y co-ordinates that tell the printer how it should move within each layer so as to draw the object
When a layer is complete, the printer head moves up (z-axis) by a specific amount, and follows the co-ordinates as defined in the next layer
A 4th stepper motor controls the filament extrusion and retraction, essentially function as a "print" / "do not print" function
All 4 motors work to move the extruder head along the right path, extruding filament when required
Learning Points:
Every variable matters and variables are often interdependent
Everything can be customised - Print speed, layer thickness, infill density and pattern, temperature, retraction length and speed, support structures and rafts, cooling techniques, first layer specifics, etc.
Consider print orientation (i.e. whether to print an object as-is, on its side, or upside down).
Solutions to most issues are readily available online
Ideas for development:
Modified and "upgraded" parts for our printer are available online (i.e. fan, damper, tensioner, auto-level).
Some of these modifications improve print quality. Others claim to make the printer run quieter.
Things we are happy with:
It works
We've calibrated it properly - a 2cm model prints as a 2cm object
Printing is cheap (PLA costs $10/kg on Taobao)
We have successfully printed objects useful for work and daily life such as a tap key, christmas decorations, a bottle opener and a tablet stand.
