The Ultimate 3D Printing Guide : 6 Methods You Should Know

Don't let the fancy names fool you, the technology is not as complicated as you might think!

3d printing, also known as additive manufacturing, is a process that does exactly what the name says it does which is 3 dimensional printing meaning printing actual objects instead of the printing we are all accustomed to which is the 2 dimensional images we see on our printers at home.

 However, some of the types of machines perform an action similar to 2d printing except 3d printing machines print multiple layers which result in a 3 dimensional object compared to the 2d printers that print only one layer of ink on a piece of paper.

Even though 3d printing did become very popular among consumers and the mainstream media until recent years, the technology has actually been around since the 1980s, but it was of course in a less advanced form back then compared to now.

 The use of the technology in the 1980s was more for the purpose of manufacturing and mass production compared to the newer technologies that are becoming more and more household friendly for consumers to create their own 3d objects in their homes for an affordable price.

A number of various 3d printing technologies currently exist and more are being developed as I type this post to make the process more efficient, low cost, and precise in regards to object dimensions.
Currently, there are 6 different types of 3d printing and all of them contain their own specific type of technologies which are explained below.

Types of 3d Printing 

Extrusion

What is extrusion you might ask? 

Well it is actually very simple. 

Extrusion is the process of forcing a usually soft and flexible material through an end piece known as a die (very similar to a garden hose nozzle) which is heated to soften the material being pushed through to create an object in layers. I like to tell people to compare it to how you would put icing on a cake with the bags that you push the icing through. (Yes it is really that simple even though it is sort of a fancy word!)

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Fused Deposition Modelling (FDM) – A process, which was developed by Scott Crump in the late 1980s, that creates objects in layers by pushing materials, usually thermoplastic, through a nozzle known as die (mentioned above in extrusion explanation)

   Electron Beam Freeform Fabrication (EBF) – A process developed in the NASA Langley Research Center by material research engineer Karen Taminger. 3d objects are made from EBF without requiring a special mold or die to produce the desired shape or shapes.

Granular

 Once again don’t let the fancy name granular scare you (sounds like it could be a word the ninja turtles say...maybe not) 

Anyways, just as the name says it deals with granular materials meaning grains as in grains of sand which I guess could be used by this process if the object being made is glass, but in this case the material is usually grains of powdered metal. 

Once again, this is a process that creates objects in a layered fashion by the laser heating the powdered material in the exact places, or dimensions, desired which causes the material to harden. The materials for this process are sort of expensive compared to some of the cheaper thermoplastics previously mentioned but this kind of technology is great for many industries who have an emphasis on exact measurements.

·         Direct Metal Laser Sintering (DMLS) – A process that uses a laser as the main power source to sinter materials in powder form which are usually metal. The process of sintering involves heating the powder, or other material, to create one solid object but not to the point that it turns the heated material into a liquid.

         Electron-beam melting (EBM) – a process used for producing metal parts which is well known as rapid manufacturing because of its ability to quickly produce objects with precise dimensions. EBM is a lot like previously mentioned DMLS but instead of using a laser like DMLS does, EBM uses an electron beam. (hence the name electron-beam melting)

        Selective Laser Melting (SLM) – started in 1995 at the Fraunhofer Institute in Aachen, Germany which uses a laser beam directed by mirrors that points the laser in the desired direction for building the objects.

         Selective Heat Sintering (SHS)

         Selective Laser Sintering (SLS)

Powder Bed and Inkjet Head 3d Printing

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Plaster Based 3d Printing (PP) – this process uses an inkjet print head (yes just like the inkjet printers we grew to love back in the good ole days tear sniff) which shoots out a binding material across a bed of powder (makes sense considering the name is powder bed) in specific areas that creates the 3d object. 

Once the machine is finished the leftover powder can be removed and reused for objects to be made in the future. This process, like the others, may seem kind of difficult to grasp but do not over think the process and let some of the big words like binding material fool you.

 Binding material is very similar to glue, and in this case you could think of the binding material as the glue that holds the dimensions of the object together, but do not get confused into thinking actual glue is used. (Elmer might get offended)
 

Laminated

This reminds me of art class in grade school when I would get my finest works laminated. Is this method similar? Lets take a look.

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 Laminated Object Manufacturing (LOM) – this is just like the art school lamination except instead of one sheet of plastic this process creates objects by layering adhesive-coated paper, plastic, or metals by gluing them together and having the dimensions cut with either a knife or a laser. LOM is pretty low cost since it has the ability to use paper but obviously has limited abilities compared to the other processes because of its basic nature. The technology was invented by Helisys, Inc which is a company that unfortunately no longer exists. The basic nature of LOM has it pretty much limited to only making prototypes since it does not have the ability to make hollow objects and complex geometry.

 

 Stereolithography (SLA) - started by Charles W. Hull in 1986 who patented stereolithography as a method and device for producing solid objects by printing thin layers of an ultraviolet material. (Layering once again makes an appearance in another method)

The method uses a concentrated beam of ultraviolet light which is focused on the surface of a container which is filled with a photopolymer (fancy word alert!) that is in liquid form.

 So this is where you ask “What is a photopolymer??” 

 A photopolymer is simply a large molecule that experiences a change in its properties when exposed to light, and in the case of SLA, it would be ultraviolet light.  

If you look at the words combined it starts to clear things up a little bit. Photo refers to light, poly means many, and mer means parts, but in this case the parts would obviously be molecules.

Anyway, the photopolymer liquid becomes hardened in the areas that is contacted by the ultraviolet light and the platform that the holds the liquid is lowered as more and more layers are created. Once the machine is finished, the object must be placed into a chemical bath to clean off any excess resin that might still be on the object from the process. 

After the chemical bath the object is then cured in an ultraviolet oven to make sure the object is totally hardened. It is very similar to making sure a cake has been in the oven long enough to make sure it does not fall apart when taken out.

 

   I would have to say this method is probably one of the most difficult to understand compared to the others but a video or two is sure to help!

The wide variety of 3d printing techniques is what makes these technologies very useful for almost any industry you can think of without even considering consumers using it to make various things needed in households. Some of the methods mentioned above are very expensive due to the materials they use and because of the complex measurement that an object might require such as a human heart. 

(it is pretty crazy that using a human heart as an example is no joke!) 

The military could obviously find great use with this technology for constructing things from bullets to parts of an aircraft carrier. The opportunities are really endless especially with modern technology that is more advanced everyday which makes you wonder what will be created a year from now that might seem impossible today. 

I personally think that one industry that will experience the biggest impact is definitely the medical industry. Health has always, and will always be, a major concern of human life considering it deals with keeping us alive. (kinda obvious) Anyway, countless numbers of people have experienced dramatic life changes because of a health condition that simply can’t be fixed by current medicine such as someone who has to go through amputation.

The most popular method in the 3d printing world is definitely Fused Deposition Modeling, also known as FDM, because of it’s affordability and simplicity for those who want to give the technology a try for themselves for the first time. FDM also has a number of low cost and easy to use software programs available on the internet to let people design basic objects that they want to see printed in 3d.

The other more expensive methods are bound to become more popular among larger companies in industries that can afford their machines and/or services that they offer. 

The first industry that comes to mind when considering who could take advantage of the more expensive methods of 3d printing would have to be the defense industry for a few reasons. 

First off, defense is always going to be a main concern of the country and government agencies will always have seemingly unlimited money so the high cost of expensive processes using expensive materials such as metals wouldn’t be much of a problem. 

3d printing technology would be extremely useful for all military branches especially during battle. For example, if a military base is short on ammo supplies they could simply make more with 3d printing machines as long as they have the needed materials of course.