Avoiding the pitfalls of 3D printing
I have already mentioned some advantages of 3D printing in one of the previous sections. While 3D printers can make very complex objects with ease, they're not the best solution in other cases for the following few reasons:
No efficiency gain when making multiple prints of the same model
It's expensive for parts larger than your hand, particularly on industrial printers
There is often a lot of hands-on processing of the design, both in the CAD design as well as finishing off the part
The range of materials is very limited compared to standard manufacturing
Let's discuss these points in more detail. 3D printing is expensive compared to mass manufactured parts (but not compared to one-off or hand-made parts). This is because each part takes just as long to make as the last—there is no time gained by making 50 parts versus just one part.
When doubling the size of a 3D print, you're actually increasing the time to print as well as the volume of the material by eight times. This increases the cost exponentially. For this reason, you'll often see light, airy, almost skeletal designs for 3D printing, as these decrease the volume of material needed. Creating holes in your design makes the part cheaper to print.
You can also print lower resolutions for thicker layer heights and a faster print, or higher resolutions for thinner, more detailed layers. Making each layer thinner increases the overall number of layers printed. Similar to increasing the size of a print, print time increases when printing a model at higher resolutions.
Visible layer lines are a fact of life with 3D prints. However, it is possible to get a smooth finish on your 3D printed part with some post processing work. Depending on the material, it may be tumbled, sanded, painted, or otherwise worked. This is typically done by hand—a time-consuming process.
Currently, nearly all printers just use one material. This means that if you need multiple materials in one print, you'll have to print them separately and assemble them later. Many materials are not compatible with 3D printing processes, limiting your choices even further.
