Factors to consider when establishing 3D Printing in the enterprise

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.

#5 Invest in 3D modeling software and design expertise

In addition to the printer, you will need to invest in suitable 3D modeling software as well as by having a competent design team. The choice of the tool will largely be determined by the kind of models that you wish to create as well as the knowledge of the design team. If wish to create engineering models, SolidWorks might be a better choice. If you are planning to create objects where surface modeling is sufficient, tools like 3D Studio Max or Blender will suffice.

Indicative prices of some software tools is as follows:

> Blender, Open Source, free of cost
> Anim8or, Freeware, free of cost
> Autodesk 3D Studio Max, commercial, single perpetual license $3675
> SolidWorks, commercial, standard single user license $3995
> SolidWorks, commercial, professional single user license $5490
> SolidWorks, commercial, premium single user license $7995

#6 Keep the printer in a fixed place
It is important to keep the printer in a fixed place and not move it frequently. 3D printing is a delicate task and in most cases, involves deposition of layers, one above the other. If the printer is moved often, the base plate may not remain level and the print head’s distance from it will be uneven. This will result in gaps between layers or in the worst case, the head scratching the based, damaging both.

#7 Monitor room temperature
If room is very cold, printed objects will warp because they will cool very fast. As the printer itself generates heat, good ventilation is needed. It is recommended that the printer be placed in a warm, evenly heated room or the printer be enclosed in a box.

# 8 Factor in the cost of consumables
Sustained operation of the printer will need consumables like filament, acetone (to help the object stick to the base; to touch up embellishments, if any) and tape to cover the base plate (so that the object does not stick to the print bed, glass in most cases and also to ensure the base plate does not scratch).

The indicative price of PLA and ABS filament is as below
* PLA, 1kg spool, 1.75mm, around Rs 2000/-
* PLA, 1kg spool, colour changing (Blue to White), 1.75mm, around Rs 3000/-
* ABS, 1kg spool, 2.85mm, around Rs 1800/-
* ABS, 1kg spool, 1.75mm, around Rs 2000/-

To help estimate how much filament is needed, we are listing the length of some filaments, typically used in FDM printers.  In case of PLA, a 1 kg spool of 1.75 mm is approx. 330 meters / approx. 1080 feet and a 1 kg spool of 3.00 mm is approx. 110 meters / approx. 360 feet. In case of ABS, a 1 kg spool of 1.75 mm is approx. 400 meters / approx. 1310 feet, and a 1 kg spool of 3.00 mm is approx. 130 meters / approx. 430 feet.  While knowing the length of a spool is important, it is also important to know how much material is consumed. For this purpose, we have provided information about some sample objects as seen in the image on your left.

#9 Printing large models

Irrespective of the technology used or the sophistication of the printer, it is a good idea not to print large models in one go. In most cases, ABS or PLA material is used for model creation. As it cools, previously printed parts of the object can warp due to temperature changes. Warping of models may result in abandoning of jobs and wastage. Additionally, if a flaw is noted,  the whole object will have to be printed all over again.

Conclusion
3D printing technology is becoming affordable and hence opening up a lot of opportunities for manufacturing. Most people believe that inventory management for many organizations will undergo a big change, where parts will be manufactured from raw material ‘on demand’, instead of being stocked Remote areas can also benefit from as needed parts can be manufactured on-site, instead of manufacturing them in the factory and then shipping them to the site of operation.

With 3D printing expected to play a vital role across multiple domains, it is imperative that enterprises have a good understanding of the technology, which can be achieved by solid, hands-on experimentation. This will help the enterprise use 3D printing in-house successfully and also offer it as a service. It is important to note that the old saying ‘Penny wise Pound foolish’ also holds true in the case of 3D printing. For example, if we decide to use 3D printing for things like making our own staple pins, it may turn out to be much more expensive that purchasing them from the market. Thus, before applying this technology for ‘printing’ objects, suitable cost-benefit analysis needs to be performed, in addition to procuring the correct equipment, followed by sufficient experimentation.