FDM 3D Printing

I’ve covered the manufacturing processes known as 3D printing for a while now. I’ve covered how 3D printing is impacting individuals, certain industries, and specific demographics. I haven’t really jumped into each individual branch of 3D printing just yet, so I’d like to cover a process of 3D printing which is referred to as FDM, or Fused Deposition Modeling.

This form of 3D printing was created by Stratasys, a competitive 3D printer manufacturing company. What is FDM? Fused deposition modeling is one of the simpler forms of this technology. It is simple compared to other methods, but is still pretty crazy if you ask me. Typically, 3D printing refers to a layer by layer assembly of a product, and this is no different. FDM goes something like this. As always, since all forms of this manufacturing involve CAM, or computer-aided-manufacturing, a CAD file has to be developed for a product to be manufactured. After the file is created, it will then be sent to the intelligent computer on the 3D printer. The printer will then control the jet, which shoots out material on to a designated area on the machine. The jet which spits out small amounts of material is heated to a very high temperature. FDM 3D printing processes use materials with lower melting points such as ABS, polycarbonates, or waxes. These materials will be in wire form and drawn from a coil into the heated jet. Think of fused deposition modeling processes as a computer aided hot glue gun. The coil of material serves as the glue, and the jet of the printer serves as the heated nozzle on a hot glue gun. Melted material will be placed on to the build table, and will end up becoming the final product.

As I mentioned earlier, the 3D printing method known as fused deposition modeling is a style of computer aided manufacturing, or CAM. Think of the hot glue gun analogy; imagine that the hot glue gun was held up by a machine, but controlled by a precise CAM system. This means that the jet will shift up, down, left, or right in the manor that it needs to in order to create the model. The 3D printer will take into account the 3D model provided by a designer or engineer, and it will move the ink jet where it needs to be as it spits out small increments of material. Just like traditional methods of 3D printing, it will be done in quite a few layers, as each individual is very small. Other methods of 3D printing cover the entire build envelope with layers of powder, and only certain parts of the powder are fused for the product. In these forms such as selective laser sintering (SLS), or direct metal laser sintering (DLMS), the powder is vacuumed back up into the machine and recycled, but some powder will always escape the machine which will lead to a “dusty” environment, and a minor waste of material. This powder lost is pretty trivial, but I felt it should be mentioned. With FDM processes, 100% of the material is used within the model, and none is wasted. However, the downside to FDM processes would be the lack of resolution. FDM processes just aren’t quite as detailed as 3D printing other methods. At the same time, it isn’t as fast as other methods either.