Abstract:
3D printing or additive manufacturing is a technology in which 3D objects are printed by
depositing a thin layer of material layer-by-layer until a final product is produced. In this
thesis work, it has been focused on the Fabrication of a Portable 3D Printer for the
manufacturing of sample parts by using Fused Deposition Modelling (FDM) process. After
fabricating the 3D printer, the primary process parameters such as nozzle temperature,
extrusion speed and fill density in addition to their interactions are studied. It has been
observed that these process parameters influence the dimensional accuracy & extrusion time
of the part produced by the process of Fused Deposition Modelling (FDM). The main
objective of the thesis work is to create a reliable and cost efficient 3-D printer and to
minimize the dimensional variation that usually occurs to plastic parts produced by 3D
printers. Cartesian mechanism has been used where the print bed moves in the Z direction
and the extruder moves in both the X & Y directions. To increase the performance and
printing accuracy of the 3D printer, a Bowden type extruder has been used. The 3D printing
filament that has been used is made of Polylactic acid or polylactide (PLA, Poly) which is
biodegradable thermoplastic aliphatic polyester derived from renewable resources. The
process involved 3D solid modeling to design, 3D printing with coated adhesive applied on
the printing platform, measurement of dimensional variation of the printed parts and
statistical analysis. Experiments are conducted using full factorial central composite design.
Response surface methodology based desirability analysis has been employed for
optimization of FDM process parameters namely, nozzle temperature, extrusion speed and
fill density. Mathematical models were developed and tested for accuracy & extrusion time
using Design Expert 11 software for RSM application.
