"What is 3D Printing?" It is a process in which a physical object is created from a three dimensional model. It works by heating up plastic and than layering multiple thin layers of material on top one another. When it solidifies, it will return to a hard plastic state.


It uses PLA (PolyLactic Acid) which is made form plants rich in starchlike wheat. It is 100% biodegradable and as a bonus, it smells sweet when printing.
Printing Temperature is around 210 Celsius. Softening temperature is about 60 celsius.


Pros

  • Can be painted with acrylic paints
  • More Environmental-friendly
  • Sharper Details (features, corners, surfaces)
  • Less Particle Emission

Cons

  • Can Deform because of heat (Low Melting Point)
  • Filament gets brittle over time due to moisture exposure


3D Printing Jargons

  • Support Structures
  • Overhangs
  • Bridging
  • Raft, Brim, Skirt
  • Infill & Infill Percentage
  • Resolution
  • File format

    • Support Structures are for giving the print a more defined form or a form in which the creator wants to achieve. Without it, the model won't have the wanted shape when it is being printed.

    An Overhang is when any part of a print that extends outward beyond the previous layer. It does not have any direct support.

    Bridging is an extrusion of material that horizontally links 2 vertical points without any support pieces or materials.

    Rafts are used to stabilize models with small "footprints", OR to create a foundation on which to build the upper layers of your part. Brims are used to hold down the edges of your part , which can prevent warping and help with bed adhesion. Skirts serve a useful purpose because they help prime your extruder and provide a smooth flow of filament.

    Infill is create inside the space of a print and it is created for structure works. Grid-like patterns, line or even honeycombs. As well as rectilinear or concentric patterns work best.

    In-Fill Percentage

    Low infill: 10 - 15%:

  • Fastest Print Time
  • Best used for prototyping big objects

    • Medium infill: 20 - 25%:

  • Most common method of printing
  • Fast print time
  • Recommended for finalising prototypes

    • High infill: 30 - 35%:

  • Mostly used for structure printing
  • Affect Large objects only
  • Slow Print (>3hrs)
  • Try to avoid it

    • 50 - 100% Infill

  • BARRED FROM FABLAB IMMEDIATELY
  • Excruciatingly Slow
  • Wasting of Materials

    • A higher density makes for a heavier and more solid print. In contrast, a lower density would provide a simpler and more lightweight result. Infill density can also affect a print's strength, buoyancy, and material used.

    Resolution

    100 Microns = 0.1 millimetres
    Less microns means finer and higher quality (Laso means longer print time)

    Recommended

  • Quick prototyping: 0.2 - 0.3 mm resolution, low infill(~10)
  • Final Prototyping: 0.2mm, normal infill(20%)

    • File Format

    STL

  • STL (Stereo Lithography) is a file format native to the stereo lithography CAD software created by 3D systems.
  • STL files describe only the surface greometry of a three-dimensional object without any representation of colour, texture of other common CAD model attributes.
  • Most CAD sodtware are able to explort to STL format.

    • Considerations when printing in FDM

  • It is a prototype, DO NOT USE MORE THAN 20% INFILL
  • Scaling affects prints!!!!!! (eg. 1:1 scaled objects down to the millimetres, anything less than 1mm will have problem printing)
  • Being Realistic
  • Export individual files to print, DO NOT export as a whole
  • Building a strong base (Enough surface area to create positive adhesion to the printer bed.) Adding RAFT will help when the base is too narrow
  • Grain Directions
  • Breaking of object into smaller parts to print
  • Overhangs/Holes (Anything more than 45 degree angle overhang will print as well without the use of support material)
  • Check your print preview in Slicing Softawre to makersure is good to go!

    • Overhang Testing


    This briefly demonstrates what overhang means. Starting with a straight piece with no angles followed by 15, 30, 45, 60, 75 and 90 degrees bend respectively.


    Work / Tests by other group members


    Clearance Test by Dean
    Bridging test by Rayan