Though 3D printing technology has been around since the 1980s, it has seems to have ‘exploded’ into the limelight primarily due to the availability of low-cost 3D printers, making the technology affordable and available to a lot of people. With this availability has come experimentation, with people wanting to use it across a broad spectrum of uses. These range from making nuts and bolts, chairs, mobile cases, spaceship parts and medical devices as the commonly cited uses. Some of the more esoteric uses of a 3D printer are when people build custom 3D printer to ‘print’ a house using concrete or a cake using dough.
Interest in 3D printing
With the technology of 3D printing being widely available, a lot is expected from it. Today, manufacturers of goods like washing machines need to maintain a large inventory of nuts and bolts, to attend service requests. With 3D printing, it is possible to print a part as and when a service request for it is received by the service center. Till that time, only raw material needs to be stored, thus reducing the capital cost of maintaining inventory. 3D printing also allows for rapid prototyping, wherein 3D models can be converted into scaled-down versions of the real thing, for detailed examination.
Establishing 3D printing in the enterprise
Various aspects that need to be considered to establish a 3D printing capability in the enterprise are mentioned below:
#1 Define the use
Before buying a 3D printer, it is important to define its use, as the choice of the printer will depend on its intended use. If you wish to only create prototypes of objects and models, a medium quality printer that uses plastic, can suffice. But, if the intended use of the printer is to create finished goods, a high quality printer, using materials other than plastic may be required.
#2 Choosing the printer type
Three popular printing technologies are SLS (Selective Laser Sintering), FDM (Fused Deposition Modeling) and SLA (Stereolithograhpy). SLS printers use a laser to heat and fuse together the 3D printing material – which may be glass, plastic or ceramic powder. The laser heats the material dispersed in a thin layer over the printing platform and traces cross-sections of the object to be printed. FDM printers use plastic filaments, extruded through a hot nozzle onto the table, layer-by-layer. SLA printers use a high-powered light source and a tank of light-sensitive liquid plastic. The light source hardens the plastic in the tank, one layer at a time.
In addition to the type of printer, its cost also needs to be considered. Imported desktop printers cost around $2000, while locally manufactured desktop printers cost around Rs 75,000 to Rs Rs 1.5 lakhs. High end printers can cost as high as Rs 4 lakhs.
# 3 Choosing material
Two types of plastic material is used in FDM printers, namely ABS (Acrylonitrile Butadiene Styrene) and PLA (Polylactic Acid). Both melt easily. Most users start with PLA, but move to ABS plastic, which is tougher but slightly harder to use. Choice of material largely depends on the intended use of the printed object. For prototypes, cost will be an important factor, while for making a finished product, rigidity, toughness and durability are of high importance.
#4 Experiment with the printer
After procuring the printer, it is important to get to know all its features and functionality. Experiment with various settings by printing various models as well as the same model using different settings. This will help you understand the models that can be printed. More importantly, it will also help you understand the models that cannot be printed. For example, using 0.4mm as the extrusion layer size for the filament will result in a rougher finish for an object, while using 0.2mm will create an object that is finer (but will take double the time to print the object).
Objects with overhangs need to be printed with care. For example, a whistle cannot be printed in upright position. As depicted in Figure 1, the whistle cannot be printed as the spout cannot be created by depositing material in the air, due to the air gap.
But, the whistle can be printed by rotating the model and placing it on its side as depicted in Figure 2. While it is possible to print small overhangs by depositing support material, (akin to putting a bamboo under a concrete slab) removing the material at the end of the print job may damage the object. Additionally, material will be wasted.